Fall is time to attack perennial weeds

The recent dip in the temperature likely prompted you to reach for a jacket. But the change in the weather has also instituted some subtle responses in the plant world.

Just like us, they're getting ready for winter.

Like most natural organisms, plants have their own ways of surviving the winter. Annuals produce seeds that insure survival of the species; deciduous trees move nutrients out of their leaves, which makes them change colors and then drop to the ground.

Herbaceous perennials extract sugars and minerals from their leaves before they freeze and die back. Lest you think this is a course in plant physiology, some of the most difficult weeds that you battle in your garden are herbaceous perennials, and this physiology lesson will help you defeat them.

Killing the leaves on these pesky weeds might make you feel good, but it does little to eradicate them. Mow them off, cut them off or even burn them off with your flamethrower and they come back. Only when you kill the roots will you get the upper hand.

Fall is the time to attack. Ever since the plants started growing in the spring, the dominant movement has been from the bottom up. With recent temperature drops, the movement has reversed as plants are storing next year's nutrients in their roots.

Your challenge is to get weed killer from the top of the plant to the roots.

One of the prime targets this time of year is field bindweed. Bindweed is native to Eurasia and ironically, it was sold as an ornamental in the United States in the early 1800s. It had spread throughout much of Utah and beyond by the end of that century.

Field bindweed's Latin name, Convolvulus arvensis describes it well. It is derived from convolere meaning "to entwine," and arvensis meaning "of the fields."

This weed goes by many different aliases including morning glory, wild morning glory, creeping Jenny, creeping Charlie, cornbind, greenvine and lovevine. It is so widespread that it reportedly goes by 84 different names in 29 different languages.

While addressing a weed by the correct name might not seem important in your social circle, you need to determine if you are referring to the right plant, because controls are specific to certain plants.

The Weed Science Society of America has designated an approved common name for each weed. This is in addition to the Latin or scientific name of the plant.