puncturevine 2

The enemy: Puncturevine (Tribulus terrestris)

Strategy: This is an annual weed that grows flat on the ground and can form very dense mats up to 15 feet across. This invader from Europe produces yellow flowers every four days. From this flower eight sharply pointed triangular seeds are formed that give this seed head the nickname of goathead. It starts growing in June and remains viable until the first frost if not controlled.

Puncturevine 1

Attack: This plant does not like any competition, therefore we always find it

in sandy, dry and gravely sites. We find it in our area along the railroad tracks, some baseball fields, and we have started to see on the borders of agricultural fields. This plant has probably single-handedly supported many bike tire and car tire repair shops, as it will ‘puncture’ bicycle and car tires.

Defense: Preventing this weed from growing is the best way to control it. Residual herbicides (Krovar I DF) applied in late fall or early winter can prevent the weed from growing. In sensitive sites such as the alleyways using Telar XP at 1.5 oz is very effective. If the weeds are along the edges of your fields and lawns, try to plant more grass. Digging up these plants if very effective, just keep in mind that you must get to the root of the plant as they will grow back if you just scrape them off the surface. Just roll the plant in front of you with your shovel, and when you find the root, dig it up and pick the plant up by this root and place it into your container for disposal (garbage is fine as the weed will get buried very deep in the landfills). 2,4-D is effective, but you must treat often.

To learn more, call Bonneville County Weed Superintendent Jeffrey Pettingill at 208-529-1397 or email weeds@co.bonneville.id.us.