University of Vermont Extension 
Department of Plant and Soil Science

Anytime News Article
Dr. Leonard Perry, Extension Professor
University of Vermont
Did weeds get ahead of you this year?  Still have “weeds” in your garden?  This may not be all bad, as weeds too have purposes and even can provide natural benefits.
So you think you know what a weed is?  Did you ever think "why" you have weeds?  Did you ever think about positive values and functions that weeds might provide?  In a book I’ve had for some years and enjoy rereading, Weeds, Friend or Foe?, author Sally Roth covers all aspects of weeds, both the good and the bad, how to use them as well as to control them.
As the author opens, she states that "weediness is in the eye of the beholder.  The word weed is an epithet of purely human invention; in the botanical world, it simply doesn't exist."  She goes on to point out that even plants with no seeming redeeming value such as burdock, may be of use to others such as herbalists.  So for the definition she states, "the simple answer is that a weed is a plant out of place.  When a plant interferes with the tidiness of our flower gardens, the sweep of our lawn, the size of the harvest, or even our personal well-being, it's a weed."  
This definition was reinforced when I visited with the head groundskeeper, David Mellor, at Fenway Park on maintaining turfgrass and weeds.  His example was that even the most beautiful rose, if growing on the ball field, would be considered a “weed” in this situation.
So given lemons, how can you make lemonade?  Or in this case, how can you use some of those weeds in your garden?  Some home uses include for food, herbal remedies, and in crafts.  Sometimes weeds are useful left in gardens, and often provide many benefits to wildlife.
Most have heard of dandelion wine, but perhaps not of the use of its leaves in salads and as greens.  Varieties have even been selected for this use.  The long curling and acid-rich leaves of sorrel have been used, especially in international cuisine, for a piquant flavor in soups and sauces.  Even the flowers of the invasive southern kudzu vine can be candied!
Many weeds also can be used herbally and medicinally, just make sure when doing so you know exactly what weed you are using, and how.  The same applies to using them to eat.  Sorrel can be used in small amounts for its flavor, but contains oxalic acid similar to spinach and Swiss chard.  With sorrel's higher concentration, too much can cause kidney damage. Some of the safe uses of weeds are topical, such as leaves of burdock on skin irritations, leaves of curly dock on boils, and leaves of dandelion applied as a wart remover.
Jewelweed, a tall impatiens (3 to 5 feet) with orange flowers, has become weedy in my gardens, the prolific seeds spreading in open areas and filling them by late summer.  Yet I leave it as the hummingbirds are fond of the August flowers, and the plant I’ve learned has many medicinal properties.  Native Americans and herbalists have used the sap for years for mosquito bites, bee stings, and rashes such as from stinging nettle and poison ivy.  Simply rub the sap on the skin right after contact, and keep applying it if needed. It has other fungal skin remedies too, such as for warts, and contains the active ingredient in some formulations of Preparation-H ointment.
Perhaps the easiest and most common home use of weeds is for crafts.  These may include fresh or dried arrangements.  Often weeds, or wildflowers, don't last as long though as fresh garden flowers.  They may also be pressed for botanical art.  Or use the blossoms in potpourri.
As long as weeds aren't let go to seed, becoming seed invasive (such as the purple loosestrife), or others allowed to spread by their aggressive roots and kill out weaker plants, they may help your garden.  They provide the green cover nature seems to want over bare ground, while your other plants are growing larger.  This prevents germination of more aggressive weed seeds. 
Shallow-rooted spreaders, such as ground ivy, provide a ground cover, preventing erosion, seed germination, and baking of heavy soils in the sun.  Dock and similar tap-rooted weeds open up the soil deeply, especially useful in heavy clay soils.  Clover and other legumes actually improve soil fertility, adding nitrogen.  When all is said and done, pulling weeds (especially tap-rooted ones, when pulling is easier after rains) helps loosen the soil so roots of desirable plants may grow more easily.
There are many wildlife uses for weeds, including hosting more insects than you see or can imagine.  There are more good insects than bad in gardens, many being predators of the bad, or serving as food for birds.  Small parasitic insects, also serving as biological controls for bad ones, feed on the nectar of many weed flowers.  
Many wild mammals feed on weeds.  Some weeds host the larvae of butterflies, such as the monarch larvae on milkweeds.  We all have seen bees, hummingbirds, and butterflies feeding on flower nectar of many weeds.  Especially important to these are the late season wildflowers, when not much else is in flower, such as goldenrod and aster.
Two wildlife aspects you may not think of are for materials and safety.  Birds especially use fibers and bark from weeds, even moss, for nest building in spring.  Weeds not only provide cover for wildlife, but a continuous strip or colony provides a safe corridor to move from one place to another.
You may be thinking, all these benefits sound desirable, but you don’t want your gardens and landscape to look like one big weed patch.  An easy solution is to reserve certain areas just for “weeds” (if there for a reason you can call them “wildflowers”) that you leave through the winter and spring, with mowed areas around and containing them.  Or, leave a strip along the back side of a property, a less visible area, or between other natural areas. In the case of annuals, like the jewelweed, these will die back with frost, when they can then be cleaned up.  Make sure you tell visitors you’re practicing sustainable, or environmentally-friendly gardening.

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