INSTRUCTOR: Leah Juarros

LESSON: Implementation -Straw Wattles

OBJECTIVES:

Upon completion of this lesson, participants will be able to identify sites that would benefit from treatment with straw wattles and how to install the treatment effectively.

NARRATIVE:

I. What is a Straw Wattle?

1. Otherwise known as Straw wattles also have different names: straw worms, bio-logs straw noodles.

2. Physical Make-up of a Straw Wattle

Straw wattles come in different diameters and are made of different materials. The length is more standard - 251. Diameters range from 8 -12". The outside tube can be made of jute, nylon, or photo degradeable materials. Wattles are generally stuffed with straw, rice or wheat. Each wattle weighs 35 pounds (of course this depends on the diameter - this is an average).

II. Site criteria

1. Purpose and Need

• Straw wattles are used with the same idea as contour felled logs, only where there aren't any trees. The idea is to place the wattles along the contour of the slope to stop overland flow, add roughness, and minimize erosion.

• The secondary benefit is the storing of eroded soil on site.

2. Slopes

• Slopes can be up to 70 percent. However, manufacturer recommendations vary and some maximums are to 50 percent.

3. Soil requirements

• Soils can be shallow, but not less than 8 inches.

III. Laying down the wattles

1. Purchase the product.

The first task is finding them. Supplies are low. We bought everything we could get out hands on. Production rate was 17,000 feet per week. Local farmer volunteered certified straw, but we couldn't find the tube. Tried to be innovative and had volunteers roll some mats.

2. Getting wattles to the site

Getting them to the site was not a problem. A helicopter was already on site to deliver other treatment materials. Loaded them up in a sling and set them down. Carrying them for any distance was a problem. Each wattle weighs approximately 35 pounds, the weight isn't the problem. It takes coordination and team work.

3. Basic installation

Installation of the wattles is basic. First, smooth out a shallow depression for the wattle to lay into. Second, throw away the wimp stakes that are sent with the wattles and use 1 X 1 stakes. Drive a stake through the wattle and into the ground, so the stake is at least 6 inches in the ground and about two inches above the wattle. The wattle will flatten out over time, so you don't need it any higher. Put 5 stakes in each wattle. You're done. Families can do it.

4. Design

Wattles should be placed in a checkerboard pattern with a 151 horizontal spacing and a 301 vertical spacing. Again, manufacturers have these recommendations with the products. We stretched the recommendations. If you haven't used them before, consider how contour felled logs would be placed across the slope, and then add a few.

5. Safety

There are few safety concerns with installing straw wattles. Basic tool safety with polaski, shovels, and field conditions cover it. We had no injuries at all with this, even on the steeper slopes.

V. Who can wattle?

Crews used for this treatment can be volunteers and Correctional Institute crews. Work could be contracted out, anyone can wattle. Depending on time into the site, 10-20 acres per day is reasonable for a five person crew.

V. Wattle Cost

Final cost was $729 per acre which is substantially higher than originally estimated at $570 per acre.

• Original estimate of the number of straw wattle placed per acre was doubled from 600 to 1200 feet per acre to get the desired results.

• Delays with labor force because discovery of old unexploded military ordinances and subsequent shut down of BAER operations.

VI. Wattle Effectiveness

1. The effectiveness of straw wattles was done with an 3-F Erosion Bridge and visual observations.

2. Straw wattles were effective at reducing overland flow.

3. Straw wattles were effective at storing eroded soil on site.

4. Straw wattles are degrading as claimed.

VIII. Summary

Now you are all experts in the use and installation of straw wattles. Okay, there are other experts out there. Call and talk to them about what their experience was.

At first we thought the hand trenching was just as effective and a whole lot cheaper. However, when you consider duration, the hand trenches just don't last.