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Agness Illahe FHWA Road
Federal Park Service
Site Visit – May 17, 2004
Hydroseeding Background.
The objective of the hydroseeding project at the Agness Illahe
site was to reduce first year soil erosion from disturbed cuts
and fill slopes while increasing stability for native seed to
germinate. A second objective was to evaluate several
combinations of hydromulch glue products supplied by Rantec
Company. Gene Davis of Rantec Company and Scott Riley, Umatilla
National Forest, participated in this project.
Conditions. Hydroseeding took place on October 15, 16
and 18, 2003 by Wintun Seeding and Mulching Company. Weather
conditions were dry and mild on October 15 and treated slopes
dried within 24 hours. On the afternoon of October 16, it began
to rain and the slopes shot that morning had only a few hours to
dry. Weather on October 18 was warm and dry. The cutslopes
shown in the following photographs were 1:1 or steeper slope
gradients with very gravelly sandy loam and loam soil textures.
Surface soils were dry at the time of shooting. Findings and
Discussion. It appears that most of the cutslopes that were
hydromulched had good germination and good surface soil
stability, thus meeting the objectives of this project.
Considering the steepness of the slopes and the high amount of
rainfall this site received last winter, meeting the project
objectives was an impressive feat.
The Rantec glues (Guardian and Super Tack) are dry products that
come in plastic bags. They are easy to use and required less
handling than liquid glues shipped in buckets. Compared to
another hyrdromulching project, the Chiloquin Highway, which
used five, 5-gallon buckets per slurry unit, this project used
less than 50 pounds of products per slurry unit. The added
advantages to these glues are they can be stored at any
temperature (liquid glues must be kept above 40F for best
results) and the only waste is the plastic bags (liquid glues
result in lots of buckets to dispose). For added strength, “dirtguard”,
a crosslinker, was applied to the slurry.
How these glue products compare to other products on the market
is not known. To conduct such comparisons would be expensive as
well as difficult to install in the field. Periodic monitoring
of completed projects to evaluate the effectiveness of glues and
mulches would help our understanding of the products on the
market. The monitoring protocol that Scott Riley and I are
developing will help answer the questions of plant establishment
and soil cover, however I am not sure that what we have
developed so far would answer the question of how much soil
erosion is being reduced during the plant establishment phase
from our application products and methods. The establishment
phase is a crucial period since it is a time when much of the
soil erosion takes place. In the future we might want to look
at using soil erosion monitoring methods developed by soil
scientists to evaluate the effectiveness of glues and mulches. |
