Control Puncturevine

Puncturevine is an annual weed that reproduces solely by seed. It begins sprouting in mid May or early June, if the soil temperature is high enough. The first flowers can appear within a week of germination, depending on weather conditions and soil temperature. A hard, spined, seed head soon develops and at maturity, breaks into five, spined seeds. These spiney seeds are hard and sharp enough to puncture bicycle tires. The spines help the seed to be dispersed when they stick into objects and animals, and are moved to new areas. Seeds from puncturevine plants can remain dormant in the soil for up to five years. This longevity in the soil makes it very difficult to eradicate puncturevine from an area

At Ada County Weed Control, we use herbicides containing chlorsulfuron to control puncturevine. Chlorsulfuron has both foliar and soil residual activity, but puncturevine is not usually present when this product must be applied. The residual effect of this chemical allows seeds to germinate and absorb the herbicide through the roots, destroying the new sprouts. In some areas and soil types, the chlorsulfuron is active for up to four months. Chlorsulfuron must be applied to the soil early enough to have rainfall move it into the top one-half inch of the dirt. As this chemical degrades through solar and microbial activity, and we see puncturevine appear, we switch to products that contain 2,4-D, usually in June or July. 2,4-D is very effective on punturevine, and is readily available to the homeowner. Most farm and home supply stores carry 2,4-D, usually in combination with other herbicides, that all control broad-leaved plants. There are other residual herbicides that can be effective on puncturevine, but extreme care should be used when selecting and applying these products. Most are not appropriate for use in home settings because they will control all vegetation in the areas they are applied, and have long term effects on planting, or successful tree and/or bush growth.

Puncturevine can germinate, grow, and begin to produce seed in as short a time period as two weeks. You should scout for new sprouts, and be prepared to retreat, every two weeks throughout the summer. This will ensure no plants survive to replenish the seed supply. With such a long seed dormancy and high survival rate, your weed control plan will need to be a long term one to ensure that all viable seed is gone from the soil. Check your herbicide label for correct use instructions.

Your alternative to herbicide treatments, is to cut and remove the weeds, but this can be difficult on large areas. Plants must be removed from the area and disposed of. If vines are more than a few inches long, seeds can fill from the food reserves in the cut stem, and become viable seed.

Please call our office if you have any questions concerning this or any other application program.

Equipment needed for puncturevine control includes a 2 gallon sprayer,

measuring cup and funnel,(not to be used for food purposes in the future)

and a herbicide labeled for turfgrass and storage yards.