Kitsap: Weeding out problems in the garden | Column
August 7, 2008 · 2:19 PM
A relatively new pesky weed, Birdsfoot trefoil, Lotus corniculatus, has been cropping up all over Kitsap County lately. The common name comes from the seed heads which look like tiny bird feet (even through the feet have six to eight toes). It began its rampant spread about three years ago, but it’s promising to be as noxious as some of our official “noxious weeds.” The ironic fact about this plant is it has been used in many states for deer fodder and forage for cattle and other grazing animals. It’s a forage plant that does not cause bloating. Birdsfoot trefoil was imported from Europe. Native peoples also harvested the seeds for food. It thrives in areas where rainfall is more than 20 inches a year and when temperatures are cooler. Does that sound like our area? Yes, indeed, it does.
Besides being imported for fodder and forage, many of the seeds came in with birdseed mixes. Some gardeners discovered it as a ground cover and liked the bright yellow flowers and clover-like leaves. The plant has trailing stems and will lie prostrate or climb up various supports. Stems reach 2 to 3 feet in length. The bright yellow clusters of flowers and green trailing stems and leaves remind many gardeners of scotch broom. It has been described in some literature as “trailing scotch broom without the invasiveness.” Unfortunately, this claim was very misleading. The plant behaved for several years, but now is cropping up in nearly everyone’s garden. Birds love the seeds and are helping spread the plant.
Birdsfoot trefoil, Lotus corniculatus, is in the plant family Fabaceae. It is a legume and cool-season perennial. Each pound of seeds produced contains 375,000 seeds. That’s a whole lot of seeds. The plant has one main “taproot” but running off of the root are numerous long running “hair like” roots. When we pull up the plant and tap root, these Long running roots produce even more plants. Quite the advantageous plant.
Visit www.invasive.org/browse/subject.cfm?sub+5949 to see and learn more about this pesky plant.
If you have Birdsfoot trefoil in your garden, get rid of it before it spreads. Cutting it back repeatedly will weaken it. As soon as you see it you can carefully dig it out and dispose of it. Make sure you get all the white side roots, too.
This is also the time of year when Buddleia (butterfly bush) is blooming in all its glory. If you have a Buddleia remember to harvest all the flowers before they go to seed. Buddleia davidii is on the noxious weed list, and by law it needs to be contained. Buddleia has an appealing scent and makes wonderful bouquets of cut flowers. Remember to cut your Buddleia down to the ground each fall and you’ll be able to continue enjoying this plant and not have it become a bad noxious weed problem.
The very best thing to do though is remove this plant if you can bear to do it. The next best thing is to keep all the flowers trimmed off before they go to seed. Dispose of the seed heads in the trash. Removing the flowers requires diligence, but I have confidence if you want to keep your Buddleia you’ll want to do the right thing and keep it from spreading its seeds all over Kitsap County.