BOISE -- No matter how green your thumb is, or how big your garden may be, weeds are something that just about everybody in Idaho can grow without much effort.
But there are many non-native weeds that have invaded Idaho and are threatening to take over native plants.
Today on "You Can Grow It", our meteorologist and master gardener Jim Duthie shows us a few of these noxious weeds that might be invading your garden.
Some weeds are native to Idaho, but there are many others that are considered non-native, or invasive, threatening to take over native plants. These weeds are called noxious weeds, and according to the Idaho Weed Awareness Campaign, there are 68 noxious weeds in Idaho.
Most of them grow on open expanses of public and private land, from the forests to the deserts, but a few of them can also be found in our own backyards and gardens.
Today I want to show you four of the most common noxious weeds that you might find growing in your yard, and how to identify them:
First, field bindweed, commonly known as morning glory. This isn't the pretty, brightly colored trumpet-shaped flowers that many gardeners grow on purpose. This morning glory, or bindweed, is a tough little vine, spreading by seeds and roots through flower beds and shrubs, and growing up fences and trellises. It has a small white, funnel-shaped flower and arrowhead-shaped leaves. The seeds can remain viable for up to 50 years. It's hard to pull out, since the vine wraps around other plant stems and leaves.
Second, puncturevine, better known to most of us a goatheads. This low-lying creeping plant spreads quickly to form a mat of leaves and lots of sharp little thorny burrs, which are also the seed pods. If you've ever stepped on one barefooted, you know how painful they can be. They'll stick to shoes and easily flatten a bicycle tire. This weed can sprout and grow to produce seeds within two to three weeks, and will continue to grow right up until the first freeze. Those sharp seed pods can remain viable for up to 20 years.
Third, scotch thistle or cotton thistle, can grow up to eight feet high. When it first emerges, it has a cluster of sharp-edged, prickly leaves that can grow to be quite large. It sends out a tall stem that is covered with sharp spines, and the whole plant is covered with fine hairs. The flower pods are also very spiny and open up into a blossom that resembles a cactus flower. It spreads by seeds, and the tap root goes deep into the ground, so it's hard to pull up. You'd need some tough gloves anyway because of the sharp stickers. It can grow in thick, dense stands that are practically impenetrable, due to the weeds' size and prickly nature.
Finally, poison hemlock can spread quickly to overtake small fields and empty lots. The plants grow to about three to six feet high with lacy leaves and clusters of creamy-white little flowers. The stem is usually streaked or spotted with red or purple, and the plant is often mistaken for fennel, parsley or wild carrots, and the root looks like a parsnip. But it's called poison hemlock for a reason. Eating the plants can prove fatal to people and domestic animals.
Once established, it's practically impossible to completely eradicate these weeds, but there are some chemical and organic herbicide products that will help you to control them.
If you do find them growing in your yards and gardens, your best bet is to just pull them up and dispose of them.
Because when it comes to a noxious weed, you can grow it, but none of us really wants to.
