Review of volunteer efforts on the City of Austin's Water Quality Protection Lands. Includes information on different solarization techniques and invasive plant species management.
4. Planning
๏ What is the state of the system?
๏ Environmental variables
๏ Soil (Depth, drainage, organic matter)
๏ Water (Run-on/run-off, drainage, shading)
๏ Light (Summer/winter/morning/afternoon)
๏ Organisms
๏ Habitat/Structure (short grass=droughty, tall grass=moist etc)
๏ Past history
๏ Seed bank
๏ Disturbances vs. Average Conditions
๏ What else is around
9. ๏ Solarization
๏ small plots ($)
๏ start in June for C4 grasses (Johnson Grass, KR Bluestem)
๏ July ok too
๏ August still helps but not as much
๏ Helps in part shade but less effective
๏ Black or clear plastic is fine
๏ Weighing down the edges is as effective and much less
labor intensive compared to trenching
๏ Kills everything equally, probably worth it
๏ Hogs targeted one of the solarized sites
๏ Remove plastic prior to degradation
15. Seeding
๏ Not about growing plants (though that would be niceโฆ),
actually done to remove a filter from reaching a desired
state: lack or organismal availability.
๏ Other filters: seed bank, weather conditions, light,
disturbance, etc
๏ WQPL seeding targets areas where seed bank
competition is minimal:
๏ Burned slash or brush piles where sustained heat consumed
the seed bank
๏ Previously canopied areas where full sun seed bank is not
established
๏ Rarely where soil movement occurs and seed bank is
unknown (Halloween 2013 flood)
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19. ๏ Horticultural varieties for Austin area:
๏ Green Sprangletop - Van Horn
๏ Prairie Wildrye - Lavaca
๏ Indiangrass - Lometa
๏ Eastern Gamagrass - San Marcos
๏ Eastern Gamagrass - Texas Sue (Lampasas)
๏ Sideoats โ Haskell (colony type)
๏ Big Bluestem - Earl
๏ Buffalograss - Texoka
๏ Hairy Grama - Chaparral
๏ Texas Grama - Atascosa
20.
21. Seed collection
๏ Plant species diversity improves range of acceptable
environmental conditions during germination and
establishment period
๏ Functional diversity improves range of ecosystem services
๏ Functional redundancy improves system resilience
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25. Seeding Methods
๏ Hand broadcast: consistent cover of seeds, picture
about 10 seeds per square inch as a minimum
๏ Ensure good seed to soil contact
๏ Hand rake: a few passes at least, noticeably fewer
seeds are visible. Cover with about 1/8โ to 1/4โ of
soil
๏ Seed drills especially designed for native species
are available for large scale applications
๏ Watered site: Much lower seed rate
๏ Sloped sites: wattles, blankets, berms
26. Planting
๏ Un-watered sites: expect 50% mortality for herbaceous
plants in the first summer and 90% mortality for woody
plants
๏ Bare root is often a less expensive option than potted
plants
๏ Live plants are a good way to stay ahead of seed bank in
a disturbed area, but anticipate competitive dynamics
when selecting species
๏ If seed source is available, woody plants will colonize a
site with minimal cultural inputs (weeding) and planting
may not be necessary
๏ Trees take 5 years of watering to establish
27. Maintenance
๏ Regular visits can prevent surprises, failures, and big
expenses
๏ Look for indicators of:
๏ Directional trend
๏ Thresholds
๏ When do we act?
๏ When do we wait?
๏ When are we done?
๏ When do we need a new plan?
๏ Management opportunities resulting from changing or extreme
environmental conditions
๏ Drought or flood can knock back woodies or exotics
๏ Flood deposits can bring in exotics
๏ Wet years can provide bumper crop of seed
