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Antonio Perkins Demonstrates His Technique: The Kudzu Chop

Under the general category of surgical treatments (removal of kudzu crowns by hand), the folding pruning saw is the preferred tool: A hand pronghoe is used to uncover and pry up crowns that are buried under leaves or other material, and then the saw cuts off the exposed crown. The Coalition tested a number of variations of this method during 2005 and 2006. Specific improvements were identified and adopted three different times as documented elsewhere. Thus, the current surgical treatment is the fourth generation in our constant drive to find better tools for fighting kudzu.

It became clear during 2006 that there are situations when using the flat blade ("hoe end") of a mattock was effective for removing exposed crowns after a skid loader treatment. After biomass is cleared away, and crowns are exposed, the mattock is used to chop off the crown from the root. This worked well — especially with golf ball size crowns. Next we tried using the hoe end of the hand pronghoe. This also worked well. Sharpening the cutting edges of both tools made the work easier. At that time we did not measure the rate of crown removal for this "chop" technique.

During the first half of 2006, some volunteers started using the pronged end of the 16" and 26" hand pronghoes as a crown extraction device. The prongs are driven under the kudzu crown, and then the crown is leveraged out. This is much like using a Weed Wrench, or like using a hammer to remove a nail. This approach is moderately successful. About half the time the crown fully separates from the roots, hopefully leaving behind no residual crown tissue that could regenerate into a kudzu plant.

A breakthrough occurred during June 2007 when the Spartanburg Urban Youth Corps worked with the Coalition on kudzu removal. One high school student, Antonio Perkins, liked the hand pronghoe tool, and decided to use it exclusively. Each worker was asked to count how many crowns he or she had removed. When break time came, Antonio reported that he had killed kudzu at a rate of 186 crowns per hour. This was stunning news because the previous record was 120 crowns per hour, and that was achieved under optimum conditions. We complimented Antonio on breaking the record, and asked him to demonstrate his method. He pulled taut the vines coming from an exposed crown, and then chopped below the crown with the hoe end of the pronghoe, thereby removing the crown in one motion. Antonio's success with this method showed that the slower process of carefully excavating the crown with the pronghoe, and then sawing off the crown, was sometimes unnecessary.

Antonio enjoyed the spotlight and set out to do even better after the break. We were impressed by his technique: Grab a vine, chop, move on, grab another vine, chop, and move on. Antonio was like a machine, and never used a pruning saw. We were again stunned to learn his rate of crown removal. Antonio had removed 320 crowns during the work hour — more than two and a half times the previous record which he had established an hour earlier!

This revelation led to a series of tests that were conducted during the next work session. At that session, Coalition volunteers Paul Savko, Tim Hamilton, and Steve Patton removed kudzu from the Broome High School site. This location was ideal because, like the Daniel Morgan Ave. site that Antonio worked, the skid loader and sheeting treatments had exposed many kudzu crowns. Paul confirmed the effectiveness of Antonio's method by killing 85 kudzu plants in 15 minutes, a rate of 340 crowns removed per hour. However, Paul quickly acknowledged that this pace was exhausting, and could not be maintained by typical volunteers. "It flat wears you out!" As a result, the Coalition does not recommend non-stop use, nor do we encourage volunteers to "go for the record".

We sharpened blades on other tools to evaluate them for this method. Garden and mortar hoes were tested with the idea that their long handle might eliminate the need to bend over during work. These tools are promising, but are not panaceas. The longer handles reduce the accuracy of "chops". Where one blow is typical for Antonio's method, several blows are required for long handled tools. Also, the longer tools prevent the worker from grabbing the vine to apply tension to the crown. This makes it more difficult to determine the location of the root. Vine tension holds the root in place better when it is struck by the cutting edge. Therefore, it is harder to chop off the crown without applying tension.

The mattock had similar drawbacks but delivers a stronger blow which is better suited for larger crowns. The kudzu chop cuts through surprisingly large roots, which we tested up to two inches in diameter. Workers, including Antonio, prefer the shorter 16" pronghoe over the same blade and prongs on a 26" handle.

The kudzu chop method might help when working in an uncleared kudzu patch. But productivity is much reduced because the overlying bio-mass must be removed, which interferes with swinging a tool for the chop. The pruning saw is more effective in this regard because it is less affected by a "crowded" work area. For these reasons, we expect winter work using the kudzu chop will be more productive than summer work. In cases where the crown is deeply buried, or surrounded by hard materials such as concrete or stones, the kudzu chop is not applicable.

Newt Hardie & Lou Adams
July 2007