The Announcements
View the full set of August announcements by clicking here. As more activities open up, more volunteer opportunities are coming into the chapter calendar. Opportunities and contacts, websites, and other details are available in the announcements.
COVID-19 update: With Dallas County’s return to Level Red precautions, we shifted our chapter meeting back to virtual. We’re tracking with CDC guidance and continue to encourage wearing masks indoors and social distancing.
Highlights of the meeting
This month’s camera roll featured our “Reunited” Summer Social. Thanks to Stalin SM and Alan Lusk for capturing the fun at our first in-person meeting in too long a time.
2nd Quarter Service Milestones: Surpassing her 2500 hour mark, Mary Mamantov led a pack of 15 NTMNs (see announcements) achieving new volunteer milestones. Congratulations to each of you. Your service is making a difference.
Can You Restore a Creek by Doing Nothing?
Continuing our Survivors theme this year, Kenneth Mayben led us through a lively, practical session on the role of riparian vegetation in stream restoration. Kenneth is a professional engineer, retired from a 42-year career with the Natural Resources Conservation Service (NRCS). His current business is Mayben Riparian Services.
Kenneth began with concepts of basic stream function, riparian plant characteristics, and plant communities needed for stream recovery. He reviewed bankfull flow and how floodplains serve to capture sediment, recharge the water table, and dissipate flood energy.
He discussed how streams are never static, that erosion and deposition are natural processes. A dynamic equilibrium exists in stream channels so when changes are made in the watershed or stream, the stream will adjust to fix itself.
Before getting to case studies, Kenneth introduced us to riparian Proper Functioning Condition Assessment – a whirlwind tour of the rigorous tool NRCS uses. It identifies elements of stream condition, rating sites in relation to their potential. The proper functioning condition method is interdisciplinary, tying hydrology, geomorphology, and vegetation together.
A stream in proper functioning condition has adequate vegetation, landform, and large woody material to protect the banks from excess erosion, trap and stabilize sediment, and sustain water storage. These physical functions drive desirable ecological values like water quality and wildlife habitat.
Kenneth compared the value of vegetation types in stabilizing and restoring riparian areas. Some astonishing statistics here, with spikerush providing up to 22 miles of roots per cubic foot and deergrass 65,000 pounds of root mass per acre. These values are orders of magnitude above upland species and show the importance of selecting the best communities for bank stabilization.
He also explained hindrances to healthy riparian areas. Activity too close to the bank topped the list: farming, grazing, mowing, and burning. Damage to the bank and channel by excessive traffic (vehicle and foot) and direct manipulation came next.
Long-term case studies showed surprisingly successful riparian restoration.
- Bear Creek, Central Oregon – from intermittent flows on bare bedrock to blue water trout stream in 30 years by changing grazing practices
- Bosque River near Valley Mills – channel relocated 350 feet and revegetated in 9 years following new bridge with stream-friendly pilings
- Nueces River – extensive revegetation/restoration over 14 years following ban on vehicles in riverbed and modifying grazing
- Six Mile Creek near Reno/Paris – restored/revegetated through reengineering channel, adding landform features and intensive plantings
Key takeaways: Riparian restoration by “doing nothing” (i.e. changing management instead of engineering channel reconstruction) works. Streams often show surprising resilience, especially if one is patient and willing to remove major hindrances. Careful evaluation of stream function and conditions leads to best management choices.
Going deeper: – Downloadable resources Kenneth mentioned in his talk
Texas Riparian Association workshops, classes, and email list
Feature on what you can do at home and workplace from GreenSourceDFW
Free BLM download: Riparian Area Management: Proper Functioning Condition
Reach out by email for creek evaluation from Mayben Riparian Services
We have posted the recording of the meeting here.
Thanks to our guests and members for participating in this month’s meeting. I hope all feel welcome at NTMN.
Take care,
Scott Hudson
President
North Texas Master Naturalist