Post # 24 Know your weeds.

I didn't always know that any plant could be considered a weed.  I thought that all weeds shared a similar physiology, evolution or life cycle which united them into an unpopular class of plants.  This is not true.  A weed is just a plant that, for some reason or another, people don't like: its perceived as useless, clogs underground plumbing, costs us money, mires our farm equipment, out competes more desirable plants, poisons our livestock, shades our crops, etc.  What's more, a weed in one location – intentionally killed, uprooted, and criticized – may be coveted elsewhere.  A plant's weediness really all depends on who you ask and what they want.

So ask an ecologists what they want and they will say 'diversity'.  Diversity is coveted by ecologists because, by definition, it suggests that many organisms are alive and well and it ensures an ecosystem's productivity and resilience.  Essentially, if extinction is the enemy, diversity is our greatest ally.  Ecologists, as well as anybody, know about weeds.  Here in the forests of northern Westchester there are weeds which threaten to decrease its diversity.  You may have heard them referred to as 'invasive species'.  Today's post is about one in particular: mile-a-minute Vine (Persicaria perfoliata).

A great poster showing all parts of the mile-a-minute vine.  Learn how to identify this weed in the field. 

        
Aptly named, this plant from Asia can grow, grow, grow over everything in its path.  With its little barbs (see picture) it can successfully hang onto the leaves, stems, and stalks of other plants as it rapidly grows up and over them.  Through research it has been shown to decrease local diversity...very weedy indeed.  Its an annual plant which means that it overwinters as a seed; the plant's vegetative parts do not persist for multiple years.  To stop this plant from spreading we need to halt its production of seeds.

Right now, the third week of August 2012, the mile-a-minute vine on the Armstrong Preserve are about to flower – I can see their swollen flower buds ready to erupt.  Remember back to elementary school biology – first come the flowers, then come the seeds.  In order to stop this plant from spreading we have to kill it before it makes seeds.  In other words, we have to kill it now.

Removing mile-a-minute vine is not necessarily difficult.  Using work gloves, you can easily pull the plant out of the ground.  BE SURE TO PULL OUT THE PLANT'S ROOTS.  If you break the stem, plant material left in the ground will begin to grow again.  It is inevitable to miss or break some vines, so get in the habit if revisiting sites a week or so after you pull vines, just to clean up any remaining plants.  After you pull the plant out of the ground you have to put it some place where it will desiccate and die (on a stone wall, driveway, etc.).    

A patch of densely growing mile-a-minute vine

If we miss our opportunity to kill this plant before it flowers and sets seed, it is likely to gain more traction in our area.  Patrol your property and spend an hour or two removing this ecological weed.  If you don't steward your own backyard, no one else will.  

For more information on mile-a-minute vine, see these on line resources:
http://www.nps.gov/plants/alien/fact/pepe1.htm
http://www.hort.uconn.edu/mam/
http://en.wikipedia.org/wiki/Persicaria_perfoliata