Weyerhaeuser would like you to believe their "Soil-Guard" is the 8th wonder of the world, when in fact the concept dates back to the early 70's when Bud Kay at UC Davis was playing with the idea. Let's congratulate Weyco on their marketing skill, but don't applaud too loudly yet, as I'm going to show you a) that "Soil-Guard" is priced about 6 Times its worth, b) the idea that you need to be certified is only in their mind, and c) their recommended rate of 3000 lbs/A may be inhibiting germination. And I'm going to tell you about D.Y.R.T. Guard, not a product but a process.

According to lab analysis and Weyco's MSDS page, this "baby diaper yellow" colored product consists of 88% wood fiber, 10% guar tackifier, 1% "trade secret" (corn starch), and 1% "trade secret" (gypsum).

Weyco will sell you the above formulation, mixed in one bag, supply you with all the slick brochures you want, and make you a "certified" applicator, all for the low, low price of $1.00/lb, or $2000/T, or $300/A!

Note: - certified means you learn how to mix it very slowly, as it tends to foam and cause pump cavitation. One "certified" contractor in Nevada reported to me that he was able to apply 9000 sq.ft. in 5 1/2 hours unload time — no wonder the applied cost/A. is over $5000/A! Also Note: at least one mfr. has confronted Weyco about their misleading and untrue test comparison data and has asked that all literature be withdrawn and corrected.

Soil-Guard has been on the ground now for about 6 mos. in the LA fire areas. Here's what I've seen: good erosion control (albeit, a very light rainfall last winter), much reduced germination except in low spots, i.e. existing rills and gullies. Bud Kay found in the early 70's that when you approach 3000 Ibs/A of mulch, you do indeed provide a mulching effect, which does inhibit germination rates - and you create a "rug" effect on the slope, which when saturated, can and does, slide off in whole; hence the need for the high % of tackifler.

Last week, while traveling in SoCal, I was told by an official with one of the public agencies that had used this virtually untested product, that his agency was withholding payment to the consultant who recommended Soil-Guard's wide-spread usage fter the fires.

Fact - normal hydroseeding methods and even untreated areas, are doing better than Soil-Guard treated areas.

Enter D.Y.R.T. Guard (Do it Yourself Right on Top) not a product that competes with Soil-Guard, but a logical process that works and will only cost you 1/6th the price of Soil-Guard.

If you have been in the erosion control business longer than two weeks, own a hydromulcher with a variable speed agitator, pay your bills, take pride in your work, and have the ability to think for yourself and analyze your results, then I consider you "certified." You can take the same type of ingredients, and by doing thing more than you already know how to do, make your own BONDED FIBER MATRIX.

Since Weyco does not reveal their "trade secret" ingredients, they make no claim as to their effectiveness, so I consider them unnecessary - except to protect a patent.)
You will get damned good performance with the above. However, I believe there's a trade off - for the erosion control benefit you may get reduced germination. And if you want me to mix the ingredients all together in one bag, send me another $2000.00/A. Hell, that's still a lot less money than the alternative.

More About Gypsum - again, you may sacrifice germ rate for erosion control performance, but Airtrol, by USGypsum Co,. has a 20 Year track record, is a naturally occurring mineral, has nutrient benefits, and plant growth benefits, when applied at USGS's recommended rate, will work out to:

Here's what gypsum does that wood fiber alone with tackifier does not do:

1. gypsum releases electrolytes into the percolating water which slows or prevents the formation of a seal and increases water penetration, thus decreasing the amount of runoff.
2. higher electrolyte concentration prevents breakdown of the soil aggregates at the soil surface.
3. rill formation and rill erosion are slowed by the presence of the electrolytes

These results were reported my M. Agassi, et al, in a test done in Israel in 1988 and published in Soil Science in 1990. The amount of gypsum used was about 4000 lbs/A. He later found in 1992, that the addition of about 62 lbs/A of an organic tackifier promoted deeper penetration into the aggregates, subsequently improving their stability.

The additional benefit of gypsum is that, as it dissolves in the presence of water, from rain or sprinkler, it adds calcium and sulfur, both necessary for plant cell formation. Soil-Guard's inclusion of a mere 30 lbs/A would certainly have no measurable benefit!

Airtrol gypsum, when being mixed, does not foam and cause cavitation. It forms a cementious crust with the soil that controls both water and wind erosion and provides excellent dust control.

Bottom Line?
I'd say beware of the consultant who gets paid by both the manufacturer and a public agency simultaneously to recommend anything to you. Shop around, listen to others, make suppliers reveal their ingredients to you, ask for side-by-side demos, and don't be fooled by slick brochures with big names on them.

Many times, contractors are asked to make recommendations about what has worked for them and their clients. I urge you to 'experiment with different rates of products on the same site.
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This whole newsletter was intended to present to you alternative methods of erosion control and to demonstrate that you can augment normal hydroseeding methods and expand the concept and effectiveness of those methods.

As always, I thank you for your business. My mission is to help you make us both successful.