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United States Department of the Interior

NATIONAL PARK SERVICE

Grand Canyon National Park

P.O. Box 129

Grand Canyon, Arizona 86023-0129

September 9, 2002

# MEMORANDUM

To: Karen Bepper-Dorn, Resource Management Specialist

From: Lori J. Makarick, Restoration Biologist

Subject: Exotic Plant Management Team Implementation Data

Per Ron Hiebert's request, I would like to provide you with information
about the current status of exotic plant inventories and treatment for
Grand Canyon National Park. I understand that you are compiling
information and preparing the implementation plan for the SCPN Exotic
Plant Management Team. I commend and appreciate your efforts and know
that they will be of great benefit to the protection of park resources.
Please let me know if you need any additional information.

## Exotic Plant Inventory and Survey Status

Grand Canyon National Park has been actively developing and compiling
information on exotic plant populations and threats within the park
since 1993. Over the past 9 years, the park has attempted to utilize
limited funding to control the highest priority species and to focus
additional time on surveys and monitoring.

In 1999, the Alien Plant Ranking System (APRS) was completed for 132 of
the 155 known exotic plants that occurred in the park at that time. The
majority of the "current impact" information was gleaned from the
literature; actual distribution information for each species was an
estimate based on ad hoc surveys. One of the current priorities is to
acquire actual field data, specifically on the distribution and
abundance of the top 30-40 priority species. The majority of the current
funding focuses on the control efforts, and does not allow for extensive
surveys. Upon completion of these surveys, the APRS can be updated to
include the current list of 159 exotic species documented in the park.

During 2001 and 2002, surveys were completed for the South Rim, North
Rim and Desert View areas. Populations were mapped with Trimble
GeoExplorer GPS units, and data was collected and supplied to SWEMP. In
addition to the developed zones, surveys have been completed in areas
associated with the 2000 Outlet Fire on the North Rim of the park.
During July 2002, the Haskell Team completed surveys along the South
Kaibab, North Kaibab, and Bright Angel Trails, and also along West Rim
Drive. These surveys will need to be redone in May or June 2003 due to
the drought conditions in 2002 and also the quality of the data
collected during those surveys. We have also surveyed a portion of East
Rim Drive during the 2002 season.

Since 1999, over 150 side canyons and tributaries have been surveyed for
tamarisk. We have current and sufficient information about the
distribution of that species. We also have survey information on the
distribution of ravenna grass in the river corridor. We do not have
current distribution information for any of the other high priority
species in the river corridor.

During 2003, we could utilize crews for 4-8 weeks (or longer depending
on the availability of the crew) for additional survey and data
collection. The following would be the priority survey areas during the
upcoming field season in FY2003:

-   South Entrance Road from the boundary to East Rim Drive

-   West Rim Drive (road corridor and between road and rim)

-   East Rim Drive (approximately 18 miles remain)

-   Corridor trails in the canyon (including North and South Kaibab and
    Bright Angel Trail)

-   Other inner canyon trails (including South Bass, Hermit, Tanner,
    Grandview, Hance, Thunder River and the Tonto Trail complex)

The coordination for the inner canyon surveys would have to be done well
in advance to ensure that the proper backcountry permits can be
acquired. While surveying on the South Rim, the park can provide camping
for the crews. Depending on how much funding is available, it may be
possible to complete river corridor surveys during FY2003.

### Treatment

For the past several years, the park utilized a variety of volunteers
for exotic plant control. Since 1995, the park has had a program
entitled "Alien Invaders", which is a hands-on interpretive program that
is held 3 days a week from April through October. During the program,
park visitors collect native seed and manually control exotic
populations. Other organized volunteers groups (i.e. Sierra Club,
Elderhostel, Grand Canyon Unified School District) and individuals have
also assisted with the manual control of exotic plant species. The
primary species volunteers work on are Mediterranean sage, horehound,
ravenna grass, Russian thistle, Himalaya blackberry and bull thistle.
During 2001, over 1600 individual volunteers assisted the restoration
program in the park, and for a least a few hours, each volunteer
assisted with exotic plant management.

During FY 2001 and 2002, the park received Intermountain Natural
Resource funds to support the control of the park's highest priority
species. These species required chemical control; the funding supported
a small crew to complete mapping, monitoring and control during the
field season. During the two years of funding, efforts focused on:

-   *Acroptilon repens* (Russian knapweed)

-   *Cardaria draba* (whitetop)

-   *Conium maculatum* (poison hemlock)

-   *Linaria dalmatica* (Dalmation toadflax)

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-   *Onopordum acanthuim* (Scotch thistle) -- manual removal only

The EPMT could complete follow-up control work on these species during
FY2003.

During FY 2003 and 2004, the park will receive additional Intermountain
Natural Resource funds to work on the control of the next highest
priority species, which include:

-   *Chondrilla juncea* (Rush skeletonweed)

-   *Cirsium arvense* (Canada thistle)

-   *Conyza canadensis* (Horseweed)

-   *Cynoglossum officinale* (Houndstongue)

-   *Centaurea diffusa* (Diffuse knapweed)

-   *Centaurea maculosa* (Spotted knapweed)

-   *Marrubium vulgare* (Horehound)

-   *Salvia aethiopis* (Mediterranean sage)

-   *Sorghum halapense* (Johnson grass)

-   *Tribulus terrestris* (Puncture vine)

The funding is limited, and additional assistance with these mapping and
control efforts in FY2003 would be welcomed. Additionally, new
populations have been discovered since the preparation of the project
proposal in 2001, and existing populations have spread. There would be
ample opportunity for the EPMT to assist with control actions during the
field season. The majority of the populations are in or near the park's
developed areas (South Rim Village, Desert View, and North Rim Village).
Camping for field crews can be obtained with sufficient notice. The
compliance will be completed for this work within the few months of
FY2003, and work would ideally begin in May and could continue through
the early part of August.

In FY2003, there would also be the opportunity to assist with Himalaya
Blackberry control at Indian Gardens, which is in the inner canyon about
4.5 miles down the Bright Angel trail. A control and restoration project
has been ongoing for several years; however, the park does not have a
current funding source to complete the control work and also re-read the
transects. With this project, it is important to have sufficient notice
in order for park staff to secure the necessary camping at the Indian
Gardens campground and to also ensure that the tools and supplies are
transported down by mule. The compliance for this project is completed.

During FY2004, the park will prepare a Vegetation Management Plan, which
will have an exotic plant species management sub-component. Ideally, a
programmatic compliance document will be prepared for the management
actions that will be necessary for the next 5 years. Any assistance the
EPMT could provide with the preparation of the plan or compliance would
be appreciated.