Court Opinion

ID: 4710135
Source: CourtListenerOpinion
Date Created: 2021-08-10 06:09:04.301712+00
Date Added: 2024-06-11T08:07:01.721927
License: Public Domain

Nebraska Supreme Court Online Library
www.nebraska.gov/apps-courts-epub/
08/10/2021 01:09 AM CDT

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                             Nebraska Court of Appeals Advance Sheets
                                  30 Nebraska Appellate Reports
                                           BUSH ISLAND v. KORTUM
                                             Cite as 30 Neb. App. 79

                             Bush Island, Inc., appellant, v. Ronald H.
                               and Gloria Kortum et al., appellees.
                                                   ___ N.W.2d ___

                                        Filed August 3, 2021.    No. A-20-391.

                 1. Equity: Actions: Boundaries. An action to ascertain and permanently
                    establish corners and boundaries of land under Neb. Rev. Stat. § 34-301
                    (Reissue 2016) is an equity action.
                 2. Equity: Appeal and Error. In an equity action, an appellate court
                    reviews the record de novo and reaches an independent conclusion
                    without reference to the conclusion reached by the trial court, except
                    that where credible evidence is in conflict, the appellate court will give
                    weight to the fact that the trial court saw the witnesses and observed
                    their demeanor while testifying.
                 3. Trial: Expert Witnesses: Appeal and Error. A trial court’s ruling in
                    receiving or excluding an expert’s testimony which is otherwise relevant
                    will be reversed only when there has been an abuse of discretion.
                 4. Property: Waters: Boundaries. The ownership of an island carries
                    with it the bed of the river to the center or thread of each surround-
                    ing channel.
                 5. ____: ____: ____. Where title to an island, bounded by the waters of a
                    nonnavigable stream is in one owner, and title to the land on the other
                    shores opposite the island is in other owners, the same riparian rights
                    appertain to the island as to the mainland.
                 6. Waters: Boundaries: Words and Phrases. The thread, or center, of
                    a channel is the line which would give the landowners on either side
                    access to the water, whatever its stage might be and particularly at its
                    lowest flow.
                 7. Waters: Quiet Title: Proof. A party who seeks to have title in real
                    estate quieted in him or her on the ground that it is accretion to land to
                    which that party has title has the burden of proving the accretion by a
                    preponderance of the evidence.
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          Nebraska Court of Appeals Advance Sheets
               30 Nebraska Appellate Reports
                         BUSH ISLAND v. KORTUM
                           Cite as 30 Neb. App. 79

 8. Waters: Words and Phrases. Accretion is the process of gradual and
    imperceptible addition of solid material, called alluvion, thus extending
    the shoreline out by deposits made by contiguous water.
 9. Boundaries: Waters: Title. Where title to an island in a nonnavigable
    stream is conveyed by grantee by government patent, and the land so
    conveyed is bounded by the waters of such stream, the grantee’s owner-
    ship carries with it the bed of the river to the center of the thread of each
    surrounding channel.
10. Boundaries: Time. Under the doctrine of mutual recognition and acqui-
    escence, while a boundary may be fixed in accordance with a survey,
    when a different boundary is shown to have existed between the parties
    for the 10-year statutory period, it is that boundary line which is deter-
    minative and not that of the original survey.
11. Boundaries. To claim a boundary line by acquiescence, both parties
    must have knowledge of the existence of a line as the boundary. It is
    insufficient for one party to merely establish a line and take possession
    up to that line.
12. ____. For acquiescence to operate, the other party must assent, by
    words, conduct, or silence, to a line as the boundary.
13. ____. In order to establish a boundary by acquiescence, it is not
    necessary that the acquiescence should be manifested by a conven-
    tional agreement, but recognition and acquiescence must be mutual,
    and both parties must have knowledge of the existence of a line as a
    boundary line.
14. Pleadings: Appeal and Error. Permission to amend a pleading is
    addressed to the discretion of the trial court, and an appellate court will
    not disturb the trial court’s decision absent an abuse of discretion.

   Appeal from the District Court for Merrick County: James
C. Stecker, Judge. Affirmed.

  Stephen D. Mossman and Jacob C. Garbison, of Mattson
Ricketts Law Firm, for appellant.

  David A. Jarecke and Ellen C. Kreifels, of Blankenau,
Wilmoth & Jarecke, L.L.P., and Charles W. Campbell, of
Angle, Murphy & Campbell, P.C., L.L.O., for appellees.

   Riedmann, Bishop, and Welch, Judges.
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                    BUSH ISLAND v. KORTUM
                      Cite as 30 Neb. App. 79

  Riedmann, Judge.
                       INTRODUCTION
   Bush Island, Inc., commenced this action to establish bound-
ary lines and to quiet title to certain property in its favor
and against Ronald H. Kortum, Gloria Kortum, Jacqueline
Drummond, Duane Drummond, Kathleen Fowles, Bradley
Lockenvitz, Sarah Lockenvitz, John Lockenvitz, Norman
Krug, and Sue Ellen Krug (collectively the defendants). The
defend­ants joined John Allen, Tamara Allen, Kenneth L. Vettel,
the Larry L. Sands Revocable Trust, the Nancy J. Sands
Revocable Trust, and Bruce W. Rodabaugh (collectively the
cross-­defendants) in the action as adjacent landowners. After
trial, the district court for Merrick County dismissed Bush
Island’s claims and found in favor of the defendants and cross-
defendants as to their claims. Bush Island appeals.

                       BACKGROUND
   This case involves disputes over land located on an approxi-
mately 4-mile stretch of the Platte River. The parcels of land at
issue here are generally located throughout Sections 10, 11, 14
through 17, 20, and 21, Township 12 North, Range 7 West of
the 6th P.M., primarily in Merrick County, Nebraska, but par-
tially extending into Hamilton County, Nebraska. Bush Island
owns two surveyed islands within the Platte River, known as
Islands 5 and 6, and all accretions thereto. The defendants own
various parcels of land located to the north and west of Islands
5 and 6, and the cross-defendants own parcels of land located
to the south and west of Islands 5 and 6.
   In 2014, Bush Island applied for and received approval to
participate in a federal restoration program with the Natural
Resources Conservation Service (NRCS). The application raised
questions of property boundaries, but ultimately, the defendants
did not challenge Bush Island’s application. Subsequently,
Bush Island expanded its application and applied for a sec-
ond federal project for additional compensation. The defend­
ants and cross-defendants objected to the expanded property
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                    BUSH ISLAND v. KORTUM
                      Cite as 30 Neb. App. 79

boundaries that Bush Island proposed in this application. Thus,
thereafter, Bush Island filed a petition in equity, pursuant to
Neb. Rev. Stat. § 34-301 (Reissue 2016), to establish the cor-
ners and boundaries of its property, quiet title to said property
in Bush Island, and enjoin the defendants and cross-defendants
from asserting any claim of interest in its property. It asserted
that it acquired ownership to additional lands through the proc­
ess of accretion.
   The defendants initially filed an answer and “crossclaim,”
joining the cross-defendants into the action as adjacent prop-
erty owners. Prior to trial, the defendants filed an amended
answer and cross-claim, which raised the issue of mutual
recognition and acquiescence of a boundary. Specifically, they
alleged that the defendants and Bush Island, or their respec-
tive predecessors in interest, mutually agreed upon a fence as
a boundary between their properties. Although the defendants’
pleading was titled as an amended answer and “crossclaim,” it
requested that the court establish the boundary line as to “all
indispensable parties.” During trial, the defendants sought and
received leave to file a second amended answer and “counter-
claim,” raising the issues of boundary by acquiescence as well
as an adverse possession claim.
   Trial was held over the course of 8 days in October and
November 2019. The record from trial is voluminous, con-
sisting of more than 1,600 pages of testimony and over 180
exhibits. According to the evidence presented at trial, the U.S.
General Land Office (GLO) was established by the “Land
Ordinance of 1785” and tasked with identifying, surveying,
and platting public lands. The GLO surveyed the portion of
the Platte River at issue in this case in the 1860’s, mapping
its meander corners and locating certain island masses within
the river. At that time, the GLO had a policy of surveying
only islands with an above-water surface area of at least 5
acres, so when it surveyed this stretch of the river in 1866, the
GLO identified only three islands within the river, which were
known as Islands 5, 6, and 7.
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                    BUSH ISLAND v. KORTUM
                      Cite as 30 Neb. App. 79

   After completion of the GLO surveys, Islands 5 and 6
merged into a larger island landmass, to which Bush Island
acquired the deed in 1961. Island 7 has merged into the south
bank and is no longer a separately identifiable landmass. In
addition, the channel banks have substantially changed since
the original GLO survey, resulting in significantly more land-
mass located between the banks than that which existed in
1866. As a result, given the hydrologic and geomorphologic
conditions of this reach of the Platte River, the physical land
claimed by all of the parties has gradually changed since their
original conveyances.
   There are three primary river channels in this area that have
been identified. They are the north channel, which separates at
a certain point in Section 16 into a north branch and a south
branch before they rejoin downstream; the middle channel; and
the south channel. Bush Island sought to quiet title to all prop-
erty from the north branch of the north channel to the south
channel, and beginning at the “Chapman Bridge” in Section 20
on the west extending to a fence on the east, as depicted in a
survey received into evidence as exhibit 202.
   Dr. Robert Mussetter is a hydraulic engineer with more than
40 years’ experience in river engineering and fluvial geomor-
phology. His work involves analyzing the quantities, timing,
and behavior of riverflow; the hydraulic conditions thereof; the
riverflow water’s interaction with boundary materials, erosion,
and sedimentation processes; and other things that affect the
behavior of rivers. For this case, the cross-defendants hired
Mussetter to determine the extent of any accretion ground
that could be attributed to them and to Bush Island, as well
as to locate the main thread of the river in this stretch of the
Platte River.
   Mussetter defined several terms that he used throughout
his testimony and report. He explained that according to the
“Federal Manual of Survey Instructions,” an island is defined
as a body of land that is completely surrounded by water when
the water is at the ordinary high water mark. Upland is the
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

area above the ordinary high water mark or, in other words, the
solid ground above the water’s surface. Ordinary high water
mark is a term used to identify the boundary between the bed
of the channel and the upland, and the channel is the portion of
the river below the ordinary high water mark. Accretion is the
gradual buildup of lands, either in or along a river, primarily
through the deposit of sediment.
   In order to determine the extent of the accretion ground
that Bush Island could properly claim, Mussetter examined the
original GLO survey and aerial photographs of this stretch of
the river dating back to 1938 and overlaid the historical pho-
tographs with current photographs of the area. He observed
how the original islands evolved over time and identified the
location of the channels and ordinary high water mark around
the boundaries of the ground. Mussetter explained that the bed
of the middle channel is and has historically been below the
ordinary high water mark, which defines it as a channel. Thus,
he concluded that the middle channel is and has been an active
channel and that it has been in approximately the same loca-
tion since 1938. In his report, he added that the middle channel
most likely also persisted during the period between the GLO
survey in 1866 and the 1938 aerial photograph. Therefore, he
opined that the middle channel forms the northern boundary of
Bush Island’s accretion claim.
   Mussetter additionally identified the south channel as the
south boundary of Bush Island’s accretion ground. He further
determined that the west boundary of Bush Island’s accretion
ground was the junction of the middle and south channels. In
sum, Mussetter opined that Bush Island’s accretion claim was
limited to the north by the middle channel, to the south by the
south channel, and to the west by the junction of the middle
and south channels.
   With regard to the thread of the river, Mussetter defined the
thread of a river as the part of the river that is the last to dry
up. He was asked whether there is a difference between the
thread of a river and a river channel, and he explained that
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

the thread of the river is one specific part of the river channel,
but that there can be multiple channels in the river, as in this
case. Mussetter determined that the primary thread of the river
here was in the north channel and that the secondary thread
was in the south channel.
   Thomas Riley, a civil engineer whose work focuses on
hydrology, streamflow, and watershed runoff, was hired by
the defendants to review the hydrology and hydraulics of this
stretch of the Platte River. He followed a process similar to
Mussetter’s by overlaying historical photographs with cur-
rent photographs and observed that the primary channels have
remained virtually unchanged since 1938. Riley opined that
the middle channel was an active channel from 1938 through
the present.
   There was also evidence presented at trial relating to a fence
that runs along the eastern edge of Bush Island’s property,
turns west and runs along the south branch of the north chan-
nel, and then curves south in Section 16. In their amended
answer and cross-claim, the defendants asserted that this fence
forms a mutually agreed-upon boundary between their land and
that of Bush Island, despite some of the land’s being located
north of the middle channel.
   The construction of the fence began with a 1938 survey by
Oscar Parsons, the Merrick County surveyor at the time. The
field notes to the survey provide that Uriah Bush, the owner of
Bush Island at that time, and Henry Kortum, the neighboring
landowner, requested that Parsons “run accretion lines,” and
he did so in Sections 15, 16, and 21. Ultimately, the fence was
built to be consistent with Parsons’ survey.
   In 1940, Parsons completed a survey to run accretion lines
for the part of Island 5 lying in Section 12 at that time.
Pursuant to that survey, a fence was built between Bush Island
and its neighbor to the east. There is no dispute that this fence
forms the eastern boundary of Bush Island.
   In late 2013 or early 2014, at the direction of John Cates,
a Bush Island shareholder at the time, licensed land surveyor
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

Kelly Stevens resurveyed the fence. Stevens explained that
Cates drove him around the area and that wherever there was
a transition, turn, angle, or change in the fence, he took GPS
coordinates. Once he completed the fieldwork, Stevens com-
piled the information into an aerial map, which was received
into evidence as exhibit 186. Stevens also incorporated this
information into exhibit 241, a survey that was created for
Bush Island’s 2014 NRCS application using the fence line as
its north and west boundary lines.
   Around that same time, the Merrick County assessor’s office
began evaluating its taxation assessment boundary lines. In
early 2014, Merrick County property owners were given the
option of providing information to the assessor’s office to assist
in redrawing the assessment lines. Jennifer Myers is the current
Merrick County assessor, but she worked as a clerk in the
assessor’s office in 2014. Myers testified that Cates approached
her in 2014 on behalf of Bush Island and told her that although
the west fence had been recognized by the surrounding prop-
erty owners as the boundary line, Cates wanted the boundary
line to be relocated as a result of a survey that had been com-
pleted in 2012. Ronald Kortum informed her that the fence line
had been an established boundary line between the property
owners dating back to 1965, and Bradley Lockenvitz provided
similar information that the north fence was the boundary line.
As a result of the information the assessor’s office received,
the assessment boundary lines were redrawn using the north
and west fence lines as boundary lines.
   Following trial, the district court entered a written order.
The court found that Bush Island’s accretion claim was lim-
ited to the channels that surround Islands 5 and 6. It noted
that the original Islands 5 and 6 were located between the
middle channel and the south channel and determined that
the middle channel was an active channel below the ordinary
high water mark; thus, the ground north of the middle chan-
nel could not be included as part of accretion ground that may
be claimed by Bush Island. According to the district court, it
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        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

was clear that accretion had added to the area of Islands 5 and
6; however, the legal description that Bush Island provided
to the court was greater than the accretion the court deemed
properly includable, because Bush Island sought accretion land
north to the north channel. As a result, the court held that
Bush Island failed to prove the boundaries of the accretion that
it alleged in its complaint, and therefore, it dismissed Bush
Island’s claims.
   With regard to the defendants’ claims, the district court held
that the parties recognized the fence as a mutually recognized
boundary for a period greater than 10 years. The court noted
that in 1938, Parsons was commissioned to run accretion lines
and that there was no evidence or claim that Uriah Bush lacked
notice or knowledge of the survey. Subsequent to the survey,
the fence was constructed and maintained for more than 75
years, and it not only separated cattle, but also served as an
undisputed boundary fence until Bush Island filed this law-
suit. Thus, the court found that the north and west fence was
a boundary fence between Bush Island’s and the defendants’
properties and that as a result, Bush Island’s accretion claim
was limited to the south and east of the fence as depicted in
exhibit 186. Accordingly, the district court established the
boundary line between Bush Island, the defendants, and the
cross-defendants as consistent with exhibit 241.
   Finally, the court awarded certain island property, referred to
as “Islands 1 through 8,” to the Kortums and awarded certain
accretion land located to the south and west of Islands 5 and 6
to the Allens and to the Larry L. Sands Revocable Trust and the
Nancy J. Sands Revocable Trust (collectively Sands).
   Bush Island filed a motion to alter or amend, which the dis-
trict court denied. Bush Island timely appeals.

                 ASSIGNMENTS OF ERROR
   Bush Island assigns, restated and renumbered, that the dis-
trict court erred in (1) allowing Mussetter to testify as an
expert as to matters of law; (2) holding that Bush Island was
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             30 Nebraska Appellate Reports
                    BUSH ISLAND v. KORTUM
                      Cite as 30 Neb. App. 79

required to determine the ordinary high water mark of the
channels surrounding its property in order to prevail on its
accretion claim; (3) holding that the middle channel has per-
sisted through time; (4) holding that the middle channel forms
the northern boundary of Bush Island’s accretion claim; (5)
holding that Bush Island failed to prove its accretion claim; (6)
holding that Bush Island recognized the existence of a bound-
ary fence for a period greater than 10 years; (7) finding that
Bush Island’s accretion claim is limited to the south and east
of the fence as depicted in exhibit 186; (8) considering exhibit
211 as evidence of an agreement as to the disposition of real
property; (9) holding that the defendants and cross-defendants
met their burdens to prove their boundaries; (10) finding that
Islands 1 through 8 separately existed and have been recog-
nized as separate islands for over 100 years; (11) finding that
the Kortums acquired title to Islands 1 through 8; (12) consid-
ering exhibit 205; (13) admitting exhibit 215; (14) allowing a
witness to testify that certain ovals depicted on exhibits 34,
391, and 392 were “the same”; (15) admitting page 4 of exhibit
244; (16) holding that “the Act of August 3, 1846, as amended
by the Isolated Tract Act of February 26, 1895[,] provided for
the sale of unsurveyed islands”; (17) permitting the defend­
ants to amend their counterclaim at trial; (18) finding that the
Allens and Sands acquired land by adverse possession; (19)
finding that the Allens and Sands are entitled to the accretion
north of the south channel; and (20) granting the Allens accre-
tion to land not at issue at trial.

                  STANDARD OF REVIEW
   [1,2] An action to ascertain and permanently establish cor-
ners and boundaries of land under § 34-301 is an equity action.
Babel v. Schmidt, 17 Neb. App. 400, 765 N.W.2d 227 (2009).
In an equity action, an appellate court reviews the record de
novo and reaches an independent conclusion without refer-
ence to the conclusion reached by the trial court, except that
where credible evidence is in conflict, the appellate court will
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             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

give weight to the fact that the trial court saw the witnesses and
observed their demeanor while testifying. Id.

                           ANALYSIS
Mussetter’s Testimony.
   Bush Island first assigns that the district court erred in allow-
ing Mussetter to testify as an expert as to matters of law. More
specifically, Bush Island claims that Mussetter was permitted
to provide his legal opinion as to the extent of Bush Island’s
accretion claim, which the district court then relied upon to
limit Bush Island’s accretion claim north to the middle channel,
rather than the north channel as Bush Island suggested.
   [3] Generally, a trial court’s ruling in receiving or exclud-
ing an expert’s testimony which is otherwise relevant will
be reversed only when there has been an abuse of discretion.
Woodmen of the World v. Nebraska Dept. of Rev., 299 Neb. 43,
907 N.W.2d 1 (2018). We find no abuse of discretion in the
admission of Mussetter’s testimony here.
   To support its position, Bush Island directs our attention to
Sasich v. City of Omaha, 216 Neb. 864, 347 N.W.2d 93 (1984).
There, in dicta, the Nebraska Supreme Court criticized the trial
court for admitting expert testimony from a legal scholar on
the status of zoning laws. The Supreme Court observed that
while our rules of evidence allow for expert testimony, that
testimony must be such as to assist the trier of fact to under-
stand the evidence or to determine a fact issue, and generally,
expert testimony concerning the status of the law accomplishes
neither of these goals. See id. Thus, such evidence is irrelevant
and inadmissible. See id.
   The common thread in Sasich v. City of Omaha, supra,
and its progeny is that the proferred testimony was offered
by a legal scholar or the contents of the challenged testimony
related to the interpretation of the law. See, also, Woodmen of
the World v. Nebraska Dept. of Rev., supra (upholding exclu-
sion of testimony of tax law professor regarding statutory
construction and his research and study of law in Nebraska);
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                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

State v. Merchant, 285 Neb. 456, 827 N.W.2d 473 (2013)
(reversing and remanding for new trial due to erroneous admis-
sion of expert testimony interpreting statute and opining that
defendant’s actions violated statute); Sports Courts of Omaha
v. Brower, 248 Neb. 272, 534 N.W.2d 317 (1995) (finding trial
court erred in receiving opinion testimony of law professor
concerning status of law); Kaiser v. Western R/C Flyers, 239
Neb. 624, 477 N.W.2d 557 (1991) (declining to consider expert
testimony as to interpretation of zoning ordinance).
   In the present case, however, Mussetter’s testimony did not
put forth his interpretation of the law for the court’s consider-
ation. Instead, he acknowledged reviewing relevant case law
in Nebraska in order to apply his scientific knowledge to con-
cepts such as accretion and the thread of the stream, which are
defined under Nebraska law. Thus, contrary to the cases Bush
Island relies upon, Mussetter did not provide expert testimony
as to his interpretation of the law or the status of the law;
rather, he provided his scientific expertise within his under-
standing of the confines of Nebraska law.
   To this end, at trial, Mussetter testified that in performing
his work for this case, he considered the principles and defini-
tions from published court cases and explained that doing so
was important because it provided the source of authority and
definitions that he then tied to his technical understanding of
the river to help identify the features in the river that are perti-
nent. Mussetter set forth in his report that he was asked to per-
form three specific tasks related to identification of the accre-
tion boundaries of Bush Island’s property. His report notes
that the question of whether Bush Island’s accretion claim
was valid hinges on whether all of the claimed upland beyond
the boundaries of the originally surveyed islands was formed
through accretion to the original islands or whether portions of
this land are actually separate islands that formed subsequently
to the original survey.
   Mussetter was aware that the defendants claimed ownership
of certain property north of Bush Island, and he confirmed
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             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

that he was not expressing any opinion of ownership regarding
any disputed grounds; rather, he was simply defining the extent
of the accretion claim that may legitimately be claimed. His
report additionally cautions that there may be other reasons to
limit the upstream extent of Bush Island’s property and notes
that he did not make any legal determinations regarding owner-
ship of any property that may be affected by any instruments of
title or other documents that are subject to question or dispute
by the parties.
    In its amended complaint, Bush Island asked the district
court to establish the boundaries of its property and quiet title
to said property in Bush Island. Mussetter did not opine as to
Bush Island’s ownership of any portion of property. Rather,
he explained whether the land Bush Island sought met the
scientific definition of accretion and outlined the limits of
Bush Island’s accretion claim due to the surrounding channels
according to Nebraska law. In other words, Mussetter detailed
the extent of land that Bush Island could claim as accretion
ground, but did not opine as to whether Bush Island proved
that it was entitled to ownership of that land. The testimony he
provided assisted the district court in determining the ultimate
fact issue of whether the lands Bush Island claimed were prop-
erly defined as accretion land. See Burket v. Krimlofski, 167
Neb. 45, 91 N.W.2d 57 (1958) (question of fact as to whether
accretion land belonged to defendants or plaintiffs).
    Furthermore, even though the district court agreed with
Mussetter’s conclusions as to the extent of land that Bush
Island could claim as accretion land, that was not the end of
the court’s inquiry into the issue of ownership boundaries,
because the defendants and cross-defendants raised claims of
adverse possession, mutual recognition and acquiescence, and
ownership by deed. Thus, because Mussetter did not opine on
the status or interpretation of the law and his testimony assisted
in determining a fact issue, we disagree that Mussetter’s testi-
mony constituted an impermissible legal opinion. Therefore,
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                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

the district court did not abuse its discretion in allowing
Mussetter’s testimony.
Bush Island’s Accretion Claim.
    Next, Bush Island generally argues that the district court
erred in holding that it failed to prove its accretion claim.
Specifically, Bush Island asserts that the court erred in finding
that Bush Island was required to determine the ordinary high
water mark of the channels surrounding its property, that the
middle channel has persisted through time, and that the middle
channel forms the northern boundary of its accretion claim. We
reject these arguments.
    [4-6] There is no dispute that Bush Island is the title owner
of Islands 5 and 6. In this state, the owner of an island has
title to any land between that island and the center of each
surrounding channel. See Winkle v. Mitera, 195 Neb. 821, 241
N.W.2d 329 (1976). The ownership of an island carries with it
the bed of the river to the center or thread of each surrounding
channel. Id. Where title to an island, bounded by the waters
of a nonnavigable stream is in one owner, and title to the land
on the other shores opposite the island is in other owners, the
same riparian rights appertain to the island as to the main-
land. Id. The thread, or center, of a channel is the line which
would give the landowners on either side access to the water,
whatever its stage might be and particularly at its lowest flow.
Babel v. Schmidt, 17 Neb. App. 400, 765 N.W.2d 227 (2009).
In other words, the thread of the stream is the deepest groove
or trench in the bed of a river channel, the last part of the bed
to run dry. Id.
    [7,8] A party who seeks to have title in real estate quieted in
him or her on the ground that it is accretion to land to which
that party has title has the burden of proving the accretion
by a preponderance of the evidence. Curry v. Furby, 20 Neb.
App. 736, 832 N.W.2d 880 (2013). Accretion is the process
of gradual and imperceptible addition of solid material, called
alluvion, thus extending the shoreline out by deposits made by
contiguous water. See id.
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                    BUSH ISLAND v. KORTUM
                      Cite as 30 Neb. App. 79

   In the present case, Mussetter and Riley each explained that
there are three main channels of the Platte River in the area
where Islands 5 and 6 are located: the north channel, the mid-
dle channel, and the south channel. Bush Island alleged that
the north channel formed the northern boundary of its accretion
land because the thread of the river was located in the north
channel. The district court, however, determined that the north-
ern boundary of Bush Island’s accretion claim was the middle
channel and that the middle channel was an active channel that
had persisted over time.
   Bush Island asserts that the district court erred in holding
that Bush Island was required to determine the ordinary high
water mark of the channels surrounding its property in order to
establish the boundaries of its accretion claim. The point of the
ordinary high water mark is relevant and important because, as
Mussetter explained, an island is defined as a body of land that
is completely surrounded by water at the ordinary high water
mark. He further explained that a river channel is the portion
of the river located below the ordinary high water mark and
that upland is land that exists above the ordinary high water
mark. Thus, because the owner of an island has title to any
land between the island and the center of each surrounding
channel, it is necessary to identify the ordinary high water
mark in order to define and locate the channels that surround
the island.
   As depicted on historical aerial photographs, the original
location of Islands 5 and 6 was bounded by the middle chan-
nel to the north and the south channel to the south. The dis-
trict court relied upon the opinions of Mussetter and Riley
to determine that the middle channel has persisted over time.
Mussetter and Riley each examined aerial photographs dating
back to 1938 and overlaid the historical photographs with cur-
rent photographs of the area; in doing so, they each concluded
that the middle channel is and has been an active channel that
has been in approximately the same location throughout that
time period. Mussetter additionally concluded that the middle
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channel most likely persisted during the period between the
GLO survey in 1866 and the 1938 aerial photograph.
   In our de novo review of the record, we give weight to the
fact that the district court credited Mussetter’s and Riley’s con-
clusions, and we observe that a review of the historical aerial
photographs confirms the conclusions reached by Mussetter
and Riley. Bush Island argues, however, that whether the mid-
dle channel persisted over time is irrelevant to determine the
boundaries of Bush Island’s accretion claim, asserting that the
northern boundary should lie in the north channel rather than
the middle channel. Although we agree that the evidence sup-
ports a finding that the primary thread of the stream is located
in the north channel, and that conclusion is not challenged on
appeal, we disagree that this mandates a finding that the north
channel establishes the northern boundary of Bush Island’s
accretion land.
   [9] Where title to an island in a nonnavigable stream is con-
veyed by grantee by government patent, and the land so con-
veyed is bounded by the waters of such stream, the grantee’s
ownership carries with it the bed of the river to the center or
thread of each surrounding channel. Heider v. Kautz, 165 Neb.
649, 87 N.W.2d 226 (1957) (emphasis supplied). The thread or
center of a channel must be the line which would give the own-
ers on either side access to the water, whatever its stage might
be, and particularly at its lowest flow. Id.
   We do not read this definition as requiring that the owners
on each side of a nonnavigable stream have access to water at
the lowest point in the entire surrounding area, when the area
consists of multiple channels. Rather, as explained in Heider
v. Kautz, supra, ownership extends to the center, or thread,
of each channel surrounding an island property, not necessar-
ily to the primary thread of the stream in the area. Mussetter
explained that the thread of the river is one specific part of
the river channel, the part that would be last to go dry, and
that there can be multiple channels in the river, as in this case.
Here, the channels that surround Islands 5 and 6, historically
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and currently, are the middle channel and the south channel.
Thus, the focus is on ensuring that owners on either side of
these two channels have access to the water, even at its lowest
flow, because they are the channels that border the island.
   Furthermore, by definition, accretion extends the shoreline
of land out by deposits made by contiguous water. See Curry
v. Furby, 20 Neb. App. 736, 832 N.W.2d 880 (2013). Black’s
Law Dictionary defines “contiguous” as “[t]ouching at a point
or along a boundary.” Black’s Law Dictionary 386 (10th ed.
2014). The waters contiguous to Islands 5 and 6 are the middle
channel and south channel. These are the channels that there-
fore define the boundaries of Bush Island’s accretion claim.
Accordingly, the district court properly held that Bush Island’s
accretion land is limited to the north by the middle channel and
to the south by the south channel.
   Bush Island relies on Winkle v. Mitera, 195 Neb. 821, 241
N.W.2d 329 (1976), to argue that land does not have to be
attached to be properly held to be accretive land for the owner
of an island. In that case, however, the plaintiff’s predecessor in
interest owned Giger Island and there was initially nothing but
water between the island and the surrounding channel. Thus,
when a new island arose in the channel waters, the plaintiff
was the rightful owner of it, even though it was not physically
attached to Giger Island, because it was located in an area in
which the plaintiff had an ownership interest: the area between
Giger Island and the thread of the surrounding channel.
   The present case is distinguishable because, although Bush
Island’s ownership interest extends north from Islands 5 and
6 to the middle channel, it does not go beyond that point,
because the middle channel also formed the northern bound-
ary of Islands 5 and 6 at the time Bush Island acquired its
ownership interest. Bush Island seeks title to land north of the
middle channel which is not attached to Islands 5 and 6 and is
not located in an area in which Bush Island has an ownership
interest. Thus, any land located beyond the middle channel
to the north or the south channel to the south is not properly
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classified as accretion to Islands 5 and 6. The district court
therefore did not err in declining to quiet title in Bush Island to
all of the land it sought in the amended complaint under a the-
ory of accretion. And because Bush Island failed to prove the
boundaries of the accretion that it alleged, the court correctly
denied Bush Island’s claims and dismissed its complaint.

Issues Related to Defendants.
   Bush Island raises several issues with regard to the district
court’s findings as to the defendants. Bush Island generally
argues that the court erred in concluding that the defendants
met their burden of proving the existence of a boundary fence
by mutual recognition and acquiescence and in awarding title
to Islands 1 through 8 to the Kortums. Bush Island also chal-
lenges the district court’s decision granting leave to the defend­
ants to amend their answer and counterclaim during trial. We
first address issues related to the fence.
   As explained above, the fence runs along the eastern edge
of Bush Island’s property, turns west and runs along the south
branch of the north channel, and then turns south in Section
16, running in a curved manner until approximately the south
channel, where it turns and begins to run northeast again.
The district court utilized the north and west portions of the
fence to establish the boundary between the defendants and
Bush Island.
   [10] Under the doctrine of mutual recognition and acqui-
escence, while a boundary may be fixed in accordance with
a survey, when a different boundary is shown to have existed
between the parties for the 10-year statutory period, it is that
boundary line which is determinative and not that of the origi-
nal survey. Sila v. Saunders, 274 Neb. 809, 743 N.W.2d 641
(2008). See, also, § 34-301. The rule long established in this
jurisdiction is that where a boundary, supposed to be the true
line established by the government survey, is acquiesced in by
the adjoining owners for more than 10 years, it is conclusive of
the location. Sila v. Saunders, supra.
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   [11-13] To claim a boundary line by acquiescence, both
parties must have knowledge of the existence of a line as the
boundary. Madson v. TBT Ltd. Liability Co., 12 Neb. App. 773,
686 N.W.2d 85 (2004). It is insufficient for one party to merely
establish a line and take possession up to that line. Id. For
acquiescence to operate, the other party must assent, by words,
conduct, or silence, to a line as the boundary. See id. In order
to establish a boundary by acquiescence, it is not necessary
that the acquiescence should be manifested by a conventional
agreement, but recognition and acquiescence must be mutual,
and both parties must have knowledge of the existence of a line
as a boundary line. Id.
   In the present case, the fence was constructed pursuant to
the 1938 and 1940 surveys by Parsons. Bush Island admits
that the east portion of the fence forms its eastern boundary,
despite the fact that the east fence is a continuous fence that
was constructed in the same timeframe as the north fence and
surveyed by the same surveyor. The fact that Parsons com-
pleted these surveys and that fences were constructed accord-
ing to the ­surveys is uncontroverted. What is disputed, how-
ever, is whether Bush Island acquiesced to the north and west
fences as the boundary separating its property from that of the
defendants.
   The evidence is clear that the defendants considered the
fence to be the boundary between their properties and Bush
Island’s. Ronald Kortum, Bradley Lockenvitz, Samuel Krug,
and Norma Krug each testified as to their understanding,
dating back decades, that the fence was the boundary line.
Ronald Kortum explained that as far back as 1984, he always
recognized the fence as the boundary of his land. Bradley
Lockenvitz, who was born in 1951, explained that he “would
say that the neighborhood has lived by [the 1938] survey
[boundaries] all of [his] life.” He recalled his grandfather
told him that the other side of the fence was Bush Island’s
property. Likewise, Norman Krug testified that his father told
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him not to cross the fence because the property on the other
side belonged to Bush Island.
   The defendants additionally described utilizing their land
as far south as the fence in various manners such as grazing
cattle, hunting, fishing, and camping and asserted that no one
from Bush Island ever objected to their doing so. Norman Krug
testified that he was not aware of any claims by Bush Island
that it owned any land north of the fence line and that between
1955 and 2010, he never encountered anyone from Bush Island
on his portion of the land. Norman Krug also recalled, dating
back to 1965, that his father grazed cattle north of the fence
and that Bush Island had cattle south of the fence. Similarly,
Bradley Lockenvitz detailed his use of his family’s land as a
teenager and young adult, venturing as far south as the fence.
He recalled walking west along the north fence and that at
some point, the fence crosses the south branch of the north
channel, so he could walk up the channel because it was then
located north of the fence on what he considered to be his fam-
ily’s property.
   There was also evidence presented that would support a
finding that Bush Island knew of and acquiesced to the fence
as its northern and western boundary. Cates’ son, a current
Bush Island shareholder, testified that he went with his father
to locate and identify the north fence during the pendency
of these proceedings. He and his father knew of and had no
dispute about the location of the fence. Cates explained in
his deposition that he helped maintain the west fence in the
1960’s and 1970’s. He admitted that the fence helped keep his
cattle in and that he “ran cattle” until 1977 everywhere east
of the west fence. Over the last 50 years, Bush Island erected
numerous deer huts or hunting huts on its property, but did
not locate any huts north of the north fence. In addition, Bush
Island used the fence line as its north and west boundary lines
in its 2014 NRCS application. Around that same time, rely-
ing on information provided by Cates and the defendants,
the Merrick County assessor’s office redrew the assessment
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boundary lines between Bush Island and the defendants based
on the north and west fence lines.
   Bush Island admits that the east fence constitutes a boundary
line between it and its eastern neighbor and that this portion of
the fence was constructed around the same time as the north
and west portions and is contiguous to the remainder of the
fence. The current president of Bush Island acknowledged his
awareness of the east, north, and west fences and the fact that
there are surveys that correspond to the location of the entire
fence. Moreover, the defendants have utilized their parcels of
land as far south as the fence line for decades without objection
from Bush Island. We conclude that the foregoing evidence
establishes that Bush Island recognized and acquiesced to the
fence as a boundary line for more than 10 years.
   We recognize, as Bush Island highlights, that there is evi-
dence in the record that would support a finding that Bush
Island did not consider the fence to be a boundary line. The
district court also recognized this controversy, finding some
of Bush Island’s evidence and arguments to be “remarkable,”
inconsistent, and not credible. Because the credible evidence
is in conflict, we give weight to the fact that the district court
saw the witnesses and observed their demeanor while testify-
ing and found the defendants’ evidence to be more credible
and persuasive. See Babel v. Schmidt, 17 Neb. App. 400, 765
N.W.2d 227 (2009). We therefore find that the district court
did not err in establishing the fence as the boundary line
between Bush Island and the defendants by mutual recognition
and acquiescence.
   Bush Island additionally asserts that it was the defendants’
burden to prove that the 1938 survey and accompanying field
notes represented a boundary agreement or mutual acquies-
cence. In our view of the evidence, it is not the survey itself
that constitutes a boundary agreement. Rather, Uriah Bush and
Henry Kortum requested the survey, Parsons completed it, and
then a fence was built pursuant to the boundaries established
by the survey. The 1940 survey followed a similar procedure.
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Thereafter, the parties were aware of the existence and location
of the fence. For acquiescence to operate, the other party must
assent, by words, conduct, or silence, to a line as the bound-
ary. See Madson v. TBT Ltd. Liability Co., 12 Neb. App. 773,
686 N.W.2d 85 (2004). Bush Island’s words in 2014 leading
the Merrick County assessor’s office to use the fence as its
assessment boundary line, conduct of remaining to the east and
south of the fence, and use of the fence as a boundary line in
its NRCS application, as well as its silence in not objecting
to the defendants’ utilizing land as far south as the fence line,
support a finding that Bush Island acquiesced to the fence as a
boundary line. Thus, the defendants need not establish that the
survey itself constituted a boundary agreement.
   Finally, with regard to the fence, Bush Island contends that
the defendants failed to meet their burden to establish the
boundary line. Specifically, Bush Island argues that exhibit
241, the survey the defendants presented and upon which the
court relied to establish the boundary, is not consistent with
the 1938 survey and does not accurately depict the fence. We
disagree.
   Although it was the 1938 survey that originally led to con-
struction of the fence, Stevens resurveyed the fence in late
2013 or early 2014 at the direction of Cates, including the
north and west portions, and depicted those survey lines on
exhibit 186. Stevens testified that in addition to the information
he gathered in the field, he utilized the 1938 survey to create
exhibit 186 and depicted the fence line with a pink line. With
regard to any differences between exhibit 186 and the 1938
survey, Stevens explained that the 1938 survey helped him
locate the corners of the fence and that he retraced some of the
lines from the 1938 survey to identify the fence line.
   Stevens also incorporated this information into exhibit 241,
a survey that was created for Bush Island’s 2014 NRCS appli-
cation. Bush Island claims that exhibit 241 does not depict
the fence line, because Stevens testified that he followed
“part of the fence” for his work for the NRCS application and
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testified that exhibit 241 does not incorporate the western area
depicted on exhibit 186 between the pink line and a light blue
line, which displays the Merrick County assessment bound-
ary lines.
   We note that parts of the record are difficult to follow,
including portions of Stevens’ testimony, because although it
is apparent that the witness is indicating locations on exhibits,
the witness does not sufficiently describe his or her indications
with testimony. In this instance, Stevens was asked whether
the light blue lines on exhibit 186 were also the shape of the
lines depicted on exhibit 241. According to the record, Stevens
replied, “In here, from about right there to about right there it
is (indicating).” We cannot discern from his testimony where
on the exhibit he is indicating. Stevens was then asked whether
exhibit 241 incorporated “that area between the pink fence and
the light blue” shown on exhibit 186, and he replied, “No.”
   Our review of exhibit 186 reveals two locations where the
pink and light blue lines diverge. Neither of these locations
affects the boundary fence at issue in this case. One location
is on the northeast portion of the north fence before the fence
turns south and forms Bush Island’s eastern boundary. This
portion of the fence is east of the Lockenvitzes’ property, and
thus, it separates Bush Island from a northern neighbor who
is not a party to this case. Accordingly, any evidence regard-
ing that portion of the fence does not affect the outcome of
the case.
   The other location is at the west fence. Despite Bush
Island’s argument, it is not clear from the record before us
that this is the area to which Stevens referred in his testi-
mony. And we note that the pink line depicting the west fence
is curved, whereas the light blue line depicting the county
assessment boundary is straight. The similarly located line
on exhibit 241 is also curved and appears to be in the same
location as the pink line on exhibit 186. Where credible evi-
dence is in conflict, the appellate court will give weight to the
fact that the trial court saw the witnesses and observed their
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demeanor while testifying. Babel v. Schmidt, 17 Neb. App.
400, 765 N.W.2d 227 (2009). Because the district court was
able to observe Stevens’ testimony and view his indications on
exhibit 186, we give weight to its determination that exhibit
241 accurately depicted the fence between Bush Island and
the defendants.
   We additionally reject Bush Island’s contention that the
language of the district court’s order establishing the bound-
ary line as “consistent with” exhibit 241 leaves Bush Island
unclear as to where the boundary lies. Bush Island representa-
tives are familiar with the fence and its location, and pursuant
to a request from Bush Island, Stevens resurveyed the fence
and incorporated information from his fieldwork into exhibit
241, which Bush Island utilized for its 2014 NRCS applica-
tion. The district court’s order is clear that it established the
boundary at the fence line based on its finding that the parties
agreed to such a boundary line. We therefore conclude that
the defendants met their burden of establishing the bound-
ary line.
   In addition to raising issues regarding the fence, Bush Island
assigns numerous errors related to the district court’s deci-
sion to award title to Islands 1 through 8 to the Kortums. The
district court determined that Bush Island failed to prove by
a preponderance of the evidence that land west of the west
fence which encompasses Islands 1 through 8 is accretion
to Islands 5 and 6. The court also observed that Bush Island
did not make a claim of adverse possession related to those
islands, but, regardless, that Bush Island would not have been
able to prove a claim of adverse possession because it did not
exercise exclusive possession of Islands 1 through 8 at any
time since 1965. The court therefore identified the remaining
question as whether these islands were owned by the Kortums,
the Allens, or Sands. None of these parties cross-appealed the
decision to award title to these islands to the Kortums, and
Bush Island does not challenge the court’s factual finding that
Islands 1 through 8 are located west of the west fence. Because
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we affirmed the district court’s determination that the west
fence forms the western boundary between Bush Island and the
defendants, Bush Island cannot claim ownership of Islands 1
through 8. Thus, we need not further address any issues related
to these islands.
   Bush Island’s final assigned error relating to the defendants
alleges that the district court erred in allowing the defendants
to amend their counterclaim during trial. After several days of
trial, the defendants filed a motion for leave to file a second
amended answer and amended counterclaim. The amended
pleading sought to add a specific claim of “Boundary Fence by
Adverse Possession and Acquiescence” related to land north of
the north fence and west of the west fence and asked the court
to establish the boundary line consistent with exhibit 241. The
court granted the motion and allowed the defendants to file
their amended pleading.
   [14] Permission to amend a pleading is addressed to the
discretion of the trial court, and an appellate court will not
disturb the trial court’s decision absent an abuse of discretion.
InterCall, Inc. v. Egenera, Inc., 284 Neb. 801, 824 N.W.2d 12
(2012). We find no abuse of discretion in the decision to grant
leave to amend.
   At the hearing on the motion, the defendants clarified that
their motion was filed under Neb. Ct. R. Pldg. § 6-1115(b),
which allows amendment of pleadings to conform to evidence
presented at trial and provides in relevant part
       When issues not raised by the pleadings are tried by
       express or implied consent of the parties, they shall be
       treated in all respects as if they had been raised in the
       pleadings. Such amendment of the pleadings as may be
       necessary to cause them to conform to the evidence and to
       raise these issues may be made upon motion of any party
       at any time, even after judgment; but failure so to amend
       does not affect the result of the trial of these issues.
   On appeal, Bush Island argues that it was prejudiced by the
court’s allowing the defendants to amend their counterclaim
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during trial. At the hearing on the motion to amend, however,
Bush Island acknowledged that the defendants had raised the
issue of the boundary fence in their previous pleading and
admitted that it had notice that the boundary fence had been
at issue. We agree that the defendants’ previous answer and
cross-claim raised the issue of boundary by acquiescence when
it alleged that the Kortums have title to the lands described
therein “based upon an accretion survey and mutually agreed
upon boundary of the same property, which was agreed upon
by [the Kortums] and [Bush Island], or their respective pred­
ecessors in interest” and made identical claims with respect
to the Lockenvitzes and Krugs. Although the defendants’ pre-
vious pleading was titled as an answer and “crossclaim,” it
also requested that the court establish the boundary line as to
“all indispensable parties.” Further, the district court’s order
granting the defendants leave to amend determined that the
defendants’ “original allegations relate to the fence as being
a boundary fence between the properties,” a conclusion that
Bush Island does not challenge. Thus, because the issue of the
boundary fence was raised in the defendants’ previous plead-
ing, no amendment as to that issue was necessary.
   Instead, the focus of the request for leave to amend was on
the addition of an adverse possession claim. At the hearing on
the motion to amend, Bush Island’s opposition was concen-
trated on the adverse possession claim, arguing that an adverse
possession claim “is a completely different claim than acqui-
escence to a boundary fence.” The district court’s posttrial
order, however, did not grant relief to the defendants on their
adverse possession claim, because it found in the defendants’
favor on their boundary by acquiescence claim. Therefore,
because the addition of an adverse possession claim did not
affect the outcome of trial, we reject Bush Island’s argument
that it was prejudiced by the court’s granting the defendants
leave to amend.
   Bush Island also argues that the district court erred in con-
sidering the defendants’ amended pleading, because although
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the court granted leave to amend, the defendants failed to file
the pleading. However, because this issue was not specifically
assigned as error, we do not address it. See Chafin v. Wisconsin
Province of Society of Jesus, 301 Neb. 94, 917 N.W.2d 821
(2018) (to be considered by appellate court, alleged error must
be both specifically assigned and specifically argued in brief of
party asserting error). In any event, we have concluded that no
amendment was necessary, because the claim upon which the
district court granted relief to the defendants was raised in their
previous pleading.

Issues Related to Cross-Defendants.
   In its final assignments of error, Bush Island raises several
claims regarding the cross-defendants, the Allens and Sands.
Bush Island asserts the district court erred in finding that the
Allens and Sands acquired certain land by adverse possession,
finding that they are entitled to accretion land north of the
south channel, granting the Allens accretion to land not at issue
at trial, and finding that the Allens and Sands met their burden
of establishing the boundaries for their claims.
   As discussed above, we find no error in the district court’s
determination that Bush Island’s accretion claim is limited to
the north by the middle channel and to the south by the south
channel, as outlined by Mussetter. Mussetter further explained
that based on this conclusion, the upstream, or western, limit of
the lands that Bush Island could claim as accretion is formed
at the junction of the middle channel and the south channel.
This junction is depicted on exhibit 366, a larger version of
which was received into evidence as exhibit 396. The district
court relied on these two exhibits when determining the extent
of the accretion land attributed to the Allens and Sands. These
exhibits also depict the upstream tip of Bush Island’s accretion
claim, which lies to the east of the Allens’ and Sands’ accretion
land. Because the land the district court awarded to the Allens
and Sands lies west of the western limit of Bush Island’s
accretion claim, Bush Island would not be entitled to any of
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the accretion land the district court awarded to the Allens and
Sands. As such, we need not further address Bush Island’s
claims regarding the cross-defendants.
                         CONCLUSION
   For the foregoing reasons, we find no error in the district
court’s decisions as outlined above. The district court’s order is
therefore affirmed.
                                                    Affirmed.
   Welch, Judge, concurring and dissenting.
   I concur with all portions of the majority’s opinion except
as it relates to Bush Island’s claim to quiet title to the prop-
erty surrounding the island itself. As to that claim, the district
court dismissed Bush Island’s claim in its entirety. As I read
the court’s order, it dismissed Bush Island’s claim primarily
because Bush Island attempted to claim an ownership interest
to a property line extending north of the middle channel and
west of the boundary fence constructed on or around 1938.
   As to Bush Island’s claim of ownership to a property line
north of the middle channel, the district court and the majority
conclude that Bush Island’s claim of ownership was limited
to the center of the thread of the middle channel of the Platte
River at that location. They derive support for this finding
from the proposition in Heider v. Kautz, 165 Neb. 649, 654, 87
N.W.2d 226, 230 (1957), quoting Higgins v. Adelson, 131 Neb.
820, 270 N.W. 502 (1936):
      “Where title to an island in a nonnavigable stream is con-
      veyed to a grantee by government patent, and the land so
      conveyed is bounded by the waters of such stream, the
      grantee’s ownership carries with it the bed of the river to
      the center or thread of each surrounding channel.”
   Because the evidence established that Bush Island was bor-
dered by the south channel of the Platte River on the south
and the middle channel on the north, the majority concludes
that Bush Island’s ownership extends to the bed of the center
or thread of each such surrounding channel. But, in Monument
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Farms, Inc. v. Daggett, 2 Neb. App. 988, 995, 520 N.W.2d 556,
562 (1994), this court also held:
      The thread or center of a channel, as the term is employed,
      must be the line which would give the owners on either
      side access to the water, whatever its stage might be, and
      particularly at its lowest flow. State v. Ecklund, 147 Neb.
      508, 23 N.W.2d 782 (1946). In other words, the thread of
      the stream is the deepest groove or trench in the bed of a
      river channel, the last part of the bed to run dry. Where
      the thread of a stream is the boundary between estates and
      that stream has two channels, the thread of the main chan-
      nel is the boundary between the estates. See Hardt v. Orr,
      142 Neb. 460, 6 N.W.2d 589 (1942).
   It is the latter proposition of law which applies here. Bush
Island and the estates on the north claim ownership interest in
property between them. As to those estates, the nonnavigable
stream, in this case the Platte River, has two channels between
those two estates—the middle channel and the north channel.
As between those two channels, the evidence unequivocally
established that the north channel was the main channel, or
the last to go dry. Under these circumstances, the thread of
the north channel becomes the boundary between the estates.
To hold otherwise would, in my opinion, contradict our prior
authority on the subject. Even though there may have been
some existing land between the middle channel and the north
channel when the GLO first surveyed this stretch of river in
the 1860’s, that land apparently was not separately identified
as an island, because it did not qualify with the GLO’s policy
of surveying only those islands with above water surface areas
of at least 5 acres, while what would become Bush Island’s
property did so qualify. Because that property qualified as
an island followed by a conveyance by government patent,
the owner of Bush Island was then entitled to ownership to
the bed of the main channel north of that island if more than
one channel existed. As such, Bush Island, from the time of
the original grant, was entitled to a claim of ownership to the
                              - 108 -
        Nebraska Court of Appeals Advance Sheets
             30 Nebraska Appellate Reports
                     BUSH ISLAND v. KORTUM
                       Cite as 30 Neb. App. 79

thread of the north channel—the channel that would be the last
to go dry.
   That said, the evidence also established that in or about
1938, the then owners of the surrounding properties agreed to
the erection of a boundary fence as erected in accordance with
an accretion survey performed contemporaneously. As the dis-
trict court found, the parties have since accepted that fence as
a boundary fence for nearly 70 years. Because I agree that the
parties have long since adopted the fence line on the north, east,
and west as the boundary of Bush Island’s ownership interest
under the doctrine of mutual recognition and acquiescence, I
would find that Bush Island was entitled to relief in the form
of quieting title to its property bounded to the west, east, and
north by the fence as depicted on exhibit 241 and by the thread
of the south channel on the south. Stated differently, although
Bush Island had the right to claim property north of the middle
channel at one time, it agreed to limit that claim of ownership
up to the fence line by mutual recognition and acquiescence.
As to that portion of Bush Island’s claim, I would reverse the
trial court’s judgment and quiet title as indicated above.