Question
I am trying to expand my vegetable garden.  I prepared the current area (about 130sf) by removing every weed and weed root by hand.  The method was very successful, but I do not want to spend that much effort on future garden areas!  

In a previous post, titled WEED KILLER, you said: "I'm trying to get you to consider a safer, less expensive, more Earth-friendly way of wiping out Weeds -- anything from covering the area with plastic to burning it with a blow torch would be quicker, cheaper and safer than using Glyphosate."  Can you tell me more about these methods of "weed" removal (the torch and the plastic - NOT the glyphosate!)?

The plant material I am trying to remove is our excuse for "lawn" (water, mow, repeat - whatever lives lives), I wouldn't go so far as to call it grass, although there is certainly some grass in the mix.  I live in Eastern Idaho, zip 83422 (cold, dry, short growing season).

Thank you!

Answer
Solarizing, Flaming, Steaming or skilled Mulching will all get you there from here.

I.  SOLARIZING

Depending on how hot it gets in Eastern Idaho, you might have success with Solarization during the Summer.  This system is also good for destroying hostile Nematodes and bacteria along with Weeds.  It takes about a month, and is highly effective as well as chemical free.

Clemson Home & Garden Information Center posts some advice about solarizing Soil on its website:

hgic.clemson.edu/factsheets/hgic1261.htm

Wait until mid-Summer, as the hottest part of the season is about to begin.  Scalp the target area w/ a lawnmower.  Then WATER the bare Dirt and mowed region -- Clemson explains that Weed seeds 'are very heat resistant when dry.'  Cover with clear polyethylene sheets from Home Depot anchored with large rocks or cinder blocks.

See, under those clear plastic sheets from Home Depot, heat collects, and it builds and builds until it's 150 degrees under there.  The Soil heats up with it.  NOTHING survives.  Earthworms and Beetles wiggle away.  Anything that can, leaves.  1 or preferably 2 months later, all Weeds and other vegetation are history.  As they point out at Clemson, 'With increasing temperature, less time is needed to reach a lethal combination of time and temperature.'  In the end, you have a clean slate, ready to grow a chemical free Lawn.

Clemson does a few things differently, and it does not hurt to go the extra mile to get this done right.

When you think it's time, remove the plastic.  Mix in whatever things your Extension Office thinks are missing from your Soil -- and include LOTS of Organic Matter.  Because you did a Soil test before this began.

(Definition of Organic Matter: Compost, Humus, Aged Manure -- anything that conditions the Soil to boost its nutrition content and make it a happy place for Grass to live.)

University of California at Davis also posts a cheat sheet on Solarization:

vric.ucdavis.edu/veginfo/topics/soils/soilsolarization.pdf

Slightly different of course, a California version.

II. FLAMING

An updated version of the time worn Slash And Burn technique for clearing a plot, this must be done carefully -- you don't want to start a brushfire and burn the house down just to kill Weeds.  You should know what you're doing.  Keep the Fire Dept posted if you don't.

Thanks to a grant from the Propane Education & Research Council, the University of Nebraska at Lincoln is probably the most public of the research outlets to post results of their testing.  Broadleaf Weeds are most susceptible to pre-emergent flaming; Grasses are tougher.  The Propane Council has posted early findings about 'thermal agriculture' online in an article, 'Propane Crop Flaming Once Again A Popular Choice':

www.propanecouncil.org/newstemplate.aspx?id=4294

The Nebraska study aims to find the 'dose' needed to eliminate Weeds with minimal pain and suffering to crops and flowers.

'Weed Flaming' offers a lot of advantages.  It's more efficient than hand weeding.  Weeds develop no resistance to flames.  And there's no collateral damage.

A newer alternative system, 'Steaming', uses special equipment to spray superheated water over vegetation.  The braised Weeds thereby succumb almost instantly.  (The water is heated to 840 degrees F; most Weed seeds are destroyed at or below 140 degrees F.)

MULCH MATTERS

Which brings us to 'Allelopathy', a defense that involves the secretion of chemicals by a plant to repel insects or competing plants.  A recent study of the Maple Leaf was pitched last year to the Michigan Turfgrass Association by Dr Suzanne Lang, Associate Professor at Michigan State University, titled 'Organic Control of Broadleaf Weeds'.

Dr Lang wanted to find out how good a mulch made out of fallen Maple leaves would be at controlling Weeds.  Lang knew there has been concern expressed over the years about using the fallen deciduous leaves of Maple trees for mulch 'due to possible alleopathic properties of some plant tissue.'

Back in 1999, Thomas A. Nikolai and Paul E. Rieke looked into whether chemicals in Maple leaves really did have those 'alleopathic properties' to (excuse the expression) Weed out the competition.  And the answer was no -- Mulch made of Maple leaves caused 'no apparent deleterious effects to established Turfgrass.'

www.michiganturfgrass.org/uploads/Rogers_-_Mulch__MTF_2006_proposal.pdf

They predicted, however, that Maple-mulched Lawns would also have 'fewer Weeds than plots treated with Oak leaf mulch or plots that received no leaf mulch (controls).  Thus, Maple leaf mulch appeared to have potential as an organic herbicide.'

What they were saying was that Maple leaf mulch would not harm the Lawn.  But it WOULD damage growth of Weeds.

Last year, Lang published a study of the 'Effect of Mulched Maple Leaves on Common Dandelion in Established Kentucky Bluegrass.'  Research showed that Sugar Maples are good at controlling Dandelions, as well as up to 81 percent (2004).

Later studies indicated that Maple leaf mulch would provide 81 percent control of Dandelions, a broadleaf Weed.  Dr Lang wants to isolate the natural chemical in those Maple leaves that is so effective at quelching Weeds.  If you don't want to wait for the study, find yourself a Maple Tree and compost this season's fallen leaves.  Then cover your Lawn or Vegetable Garden with them.

Any questions?