A node forms in young vines about every 6" to 8", as shown in the photograph. Nodes are the source of more vines and roots. Mature vines can have nodes about every 12" to 16". June 2005.

A closeup view of developed nodes show carrot-like tap roots and rootlets (bottom), knobby crown (center), and green or brown vines (top). Severing the crown from vines and roots kills the rooted plant: Vines do not bud from roots. It is unnecessary to dig up the tap root, which can be long, deeply buried, and heavy! June and July 2005.

The following diagram illustrates the major parts of typical kudzu plants. Click on it for a larger image. Woody overwintering stems send out new vines at nodes during the growing season, whereas the non-woody "green" stems and leaves crumble to mulch at the end of the growing season. Stem nodes are the source of all vines. Nodes develop rootlets, become rooted nodes, then develop into crowns attached to carrot-like roots. All of the horizontally-oriented stems in the diagram lie at the surface of the ground, and all of the vertically-oriented lines below them are rootlets or roots growing into the ground. For example, the features labeled (A), (B), (C), and (D), are all at ground level. Some mistakenly state that kudzu has rhizomes. However, all kudzu stems begin above ground so they are not "rhizomes" but can be referred to as "stolons". Roots can weigh hundreds of pounds, and reach depths of a dozen feet in Asia, but they have less spectacular weights and depths in the United States. Kudzu has only been in the United States for about a century, whereas plants in Asia can be hundreds of years old. Kudzu also flowers, and produces seed pods.

If the above figure is confusing, here is how Jim Miller of the USDA Forest Service, a specialist on invasive plants in the Southeast, sketched out kudzu plant growth for the Coalition. The oldest plant (far left) sends out a vine to the right, that roots and sends out another vine, and so on. Click on it for a larger image. August 2007.

Once a node is rooted, it becomes a self-supporting individual plant. While seemingly self evident, this was nonetheless tested at the instigation of Coalition volunteer Paul Savko. The left photograph shows Paul (minus his head, sorry Paul!) holding a vine connecting a dense kudzu patch (background), and a colonizing sprout in an area with relatively little kudzu (left foreground). The vine connecting the sprout and its "mother" was cut, and the ends were marked with ribbons for identification during follow-up observations (right photograph). As expected, the sprout continued to grow and send out its own colonizing vines. June 2006.

The Coalition's currently favored tools for surgically removing root crowns include three-tined pronghoe, pick, and folding hand pruning saw. When the Coalition began its work, a firefighting tool called a Pulaski was the favored heavy tool for a few years. However, the axe-and-hoe head on a Pulaski is not as useful as the pick-and-hoe head on a pick. The three types of tools shown in the photograph are now always carried by Coalition volunteers for surgical root crown removal. See the summary at the bottom of this web page for more details on all three tools. August 2006.

The type of hand digger judged best for crown removal has also evolved over several years. The hand pronghoe (left) is too fragile for larger crowns. The middle two tools are much sturdier. One side is bladed for cutting, and the other side is pointed for picking away soil and prying. The tool on the right has two sides useful for picking soil away from the crown and hooking it for prying: The narrower prongs make it easier to penetrate and break up compacted clay soils than the wider blade. The wide blade is useful for heavy digging or cutting vines and roots. The objective when using these tools is to pry up a crown and cut it from vines and root, or to position the crown for cutting by the saw (see below). Currently workers prefer to carry the tool at the far right, along with a flexible bladed folding hand pruning saw. The heavy pick is carried only as needed. July 2006.

The Coalition is now beginning to experiment with power tools for jobs difficult to do by hand, or time consuming to do by hand. The rechargeable reciprocating saw shown in the photograph (18 volt, Black & Decker Firestorm, $90; plus blade for wood, $5.70) reduces a 5 minute job of cutting roots from a large crown down to 30 seconds. Thanks to Doug Perkins of Marblehead Conservancy for the suggestion! He finds that carrying 6 rechargeable batteries for his 18 volt DeWalt saw is enough charge for one hour of continuous cutting work. Please read our disclaimer. November 2006.

A gentle tug usually pops up a node that is held to the ground with small rootlets. When rootlets are larger, doing this risks leaving a piece of the crown attached to the root, which eventually regenerates as a full crown and regrows vines. Instead, to remove a larger crown it is simply a matter of slipping the flexible folding saw blade beneath the crown, and severing the crown from the attached root. The vines attached to the crown are then cut off, and the crown is placed in the sun to dry out and die. May 2006.

For larger crowns, or small buried crowns, the hand pronghoe or digger is used to pry the crown up so that the saw blade can more easily separate the crown from the root. The crown is a "knob" sitting on top of the root. Be sure to remove the entire crown! Although the root can be large, it dies without the crown. May 2006.

How many crowns can be surgically removed by a trained worker in one hour? In one test shown in the photograph, flags mark about 50 crowns that were removed from an area of ground in one hour. The ground was previously covered by a plastic sheet for a period of time to knock down vegetation. Note the rolled-back dead kudzu vines that was part of the crown removal process. More work time statistics are given at the bottom of this web page. September 2005.

The following impromptu note from Spartanburg Day School student Rob Jordan is a fun report on the experience of high school students with surgical crown removal. Thanks Rob!

Hey Mr. Newt how you doing? We have got some interesting facts for the Kudzu Coalition. By our ejumakated math we came up with 103 crowns per person at 100% capability. That was eight people avgd. from Mr. Steele to a beginner. Eight people worked as hard as they could for 15 min and agvd. those out to get around 15 in 15 minutes at 100%. We also did the math to incorporate 2/3 capacity and found that an educated kudzu killer can over 90 minutes get an estimated 68 crowns per outing. And the whole group of eight should get 545 in a trip. These are valuable statistics that can help estimate man hours. {We used 90 minutes as our template.} At two-thirds capacity people did not feel rushed or uncomfortable. We also noticed people grouped together in pairs of two or threes. Hopefully this information is something that can help estimate our long journey ahead battling the mean green consuming machine in Sparkle City. (Hopefully we wont get it all, because we wouldn't have anything to do.)

Our range was from 40 to 6 @ Peter's Creek Preserve.

Average was 17 crowns in 15 minutes. (It could have been the anxiety from exams. haha)

Most people had attended more than three battles.

We found a turtle under a toilet!

The ground was frozen sold at the beginning people kinda moaned and groaned at the beginning but we got the blood flowing after ten minutes of battle.

Dr. Newberry was awesome she is a walking Encyclopedia of knowledge, and the people really enjoy working with her.

Rob Jordan
December 2006

When following a vine and beginning to dig for a kudzu crown, the question sometimes arises how deep to dig when an obvious crown is not found. If a vine, then a crown lies further below, and more digging is necessary. If a root, then no further digging is necessary, and one can safely cut the root knowing that all crowns were higher up. However, earth-covered vines and roots can have a very similar visual appearance, although vines generally run horizontal, and roots generally run vertical. Here is a simple test discovered by Coalition volunteers in case of doubt: Scratch the vine or root with a fingernail to remove the outer skin. If the uncovered tissue is yellowish-green ("pistachio"), then the color indicates the presence of chlorophyll, and it is a vine. If orangish-yellow, then the absence of chlorophyll suggests that it is a root. However, this rule-of-thumb does not always work after the growing season ends (after first frost), or when the plant is otherwise in hibernation or in poor health.

Does surgical crown removal work? The first photograph below was taken at the Coalition test site in August 2005. Flags show locations where crowns were removed. Such locations are monitored for regrowth, in case the crown was not completely removed. The sign shows the former name of the method ("manual crown removal"), which we decided was confusing. The second photograph shows the same area May 2006, and the sign shows that kudzu has been completely eliminated by surgical crown removal.

Sometimes it is possible to chop out a crown using one hand tool if the crown is not buried deeply, so the pruning saw is unnecessary. This method, the Kudzu Chop, is described in detail on its own web page. Much faster crown removal is possible using this method.