Identify grass and how to eradicate

Asked April 19, 2019, 8:57 PM EDT

We have a grass (images attached) that grows around our oak trees which is spreading rapidly. We have tried to control by physically “weeding”. However any contact with skin causes a burning rash. We would appreciate if you could identify and help us find a means to eradicate.

Polk County Oregon weed issues wild garlic allium

1 Response

Unfortunately, your weed isn't grass. It is wild garlic, Allium vineale.

Wild garlic is challenging to eradicate. It grows from a small bulb and also produces a flower head with pre-sprouted seedlings that will begin to grow when they land on soil.

Although “Wild garlic control in nursery crops” is written for large-scale commercial growers, it explains the challenges you will encounter. It says, among other things, “Wild garlic bulbs can persist dormant in soil for 6 years. Nothing sprayed above ground can kill dormant bulbs beneath the soil surface. Complete control in a field infested with wild garlic cannot occur in a single year. Persistent management for at least 3 or 4 years (maybe as many as 6 years) is necessary to obtain complete control.” The document also has good images of the plants, the bulbs, and the flower heads. (http://oregonstate.edu/dept/nursery-weeds/feature_articles/wild_garlic_email/wild_garlic.html)

Here are your guidelines:

- Ask at the garden center for an herbicide containing 2,4-D

- Caution: Even a small dose of the herbicide can seriously damage your trees.

- Do not spray; instead use a wipe-on application to treat the garlic; a small paintbrush, used only for that purpose, is helpful.

- Caution: You must avoid getting any of the herbicide on your trees.

- It is very important to treat for consecutive years to effectively reduce the garlic.

- Time to apply: Every year, in early spring, preferably mid-April, before the garlic is 8 inches tall.

- Remove bloom heads as soon as you see them, then discard in the trash or burn pile; do not compost them.

- While working in the infested area, protect your skin with long pants, long sleeves, and gloves.

- To be successful battling wild garlic, you must be persistent for a number of consecutive years.

Good luck!