Atlanta tri-weekly journal. [volume] (Atlanta, Ga.) 1920-19??, 1922-12-05
Controlling Rosette in Pecan
Orchards

Pecan orcharding promises to be
come one of our most important
state enterprises. This most defect
able among all the cultivated varie-
ties Of nut trees is steadily growing
IN public favor. AS a result. in
creasing areas Of our lands are each
year being planted to this import
ant economic tree. Our investments
In pecan ofcharding ere, therefore,
attaining proportions where any.
thlng which affects the growth or
development of this tree becomes a
matter of wide concern. Fortunate.
ly, the pecan has not suffered very
much as yet from the attacks of a
great variety of insects or fungous
pests. 1t appears, however, that
there is one disease attacking it
which has done a great deal Of DAM
age in the past. 1t is known as the
Rosette. A good deal of effort to
prevent its spread and determine the
best means of controlling has been
made. On account of it's Importance,
1t has been subject Of a great deal
OF study on the part of the horti-
cultural division of the Georgia State
college of Agriculture. The results
erence to this matter by J. William
flror have recently been completed.
Ills findings are certain to be of
general interest and concern to all
those who are cultivating pecans.
The rosette is generally considered
the most serious trouble of the Pc
can. This opinion seems to be justi-
lied by the facts, and is held by
nAnU
clallsts. Probably 10 to 20 per cent
OF the pecans planted in orchards
IN the southeastern United States
nave shown this trouble.
The writer has a record Of a block
OF $50 pecan trees-most of which
are of the Stuart variety, some few
Frotschers and Teche-1S3 of which
We're rosetted severely enough to
nave some dead twigs, and ia of
which were rosetted, but not suf-
Ilclently to have dead twigs. This
DOCK of trees is located in Jeffer-
Son county, Georgia. The record
gwen above is for the year 1915.
records taken of the same block
during 1913 and 1914 show almost
the same severity of rosette. In
1919 this same block had 279 trees
with dead twigs and ninety-seven TO-
setted without dead twigs. Fifty
tour per cent of this block was ro.
setted in 1919. This is too great
handicap to the grower.
There are very few orchards in
the state of Georgia, which are en-
tlrely free from the rosette. It is
possible that 10 to Is per cent of all
the trees of budded varieties in the
state OF Georgia are non-productive
because of the rosette trouble. If
this is true, and it seems to be
conservative estimate, this disease is
demanding annually 10 to Is per
cent deduction from the productive
value of the orchards.
The pecan is a terminal bearer.
Shoots are produced from special
budS borne at the end of the pre-
VlouS seasons grOWths. Nuts are
not borne on spurs, as fruit is borne
on the apple; nor from lateral buds,
like the peach. Any trouble that
starts with the seasons growth seri-
pusly affects the next seasons crop.
The rosette begins it's attack on the
outmost twigs Of the tree. It is not
unusual to see a tree with some of
the tWIgs rosetted, while the remain
ing twigs are healthy. The twigs
which are rosetted do not bear mer-
charitable nuts.
In addition to cutting down the
production, the rosette keeps a tree
small and gives it a very ugly ap-
pearance. Also the rosette wealens
the tree by virtue of the fact that
it interfered with the proper develop
ment of the foliage. 1t is we'll known