Time to cut Japanese barberry

Its official, spring has arrived: the pheobes are back, I heard an american robin singing, the leaves of the trout lily have emerged and I saw a red maple in bloom.  In the coming weeks the forest will green out and it will start with the Japanese barberry.  This shrub (originally from Japan and eastern Asia) is one of the first plants to push forth its leaves.  For someone suffering from the winter blues the early-spring color of Japanese barberry can be quite welcoming but unfortunately there is a downside to its leaves.  

It turns out that Japanese barberry is able to create a microclimate that is favorable to the black footed tick, the insect that transmits Lyme disease through its bite.  Under the dense shrub, humidity stays high enough to allow for active ticks that would otherwise have to burrow into the moist soil to escape desiccation.  This blog post encapsulates the recent findings of UCONN professors who say that managing Japanese barberry will reduce Lyme disease risk.  This blog post presents additional findings.      

Japanese barberry leafs out while most of the forest remains dormant 

I have spent the last few weekends removing Japanese barberry from the Armstrong Preserve.  Besides harboring disease-carrying insects, this plant is well known for being an invasive plant capable of lowering plant biodiversity and altering soil characteristics.  To read more about the plant's invasive behavior read here.  Most of the literature offers a variety of options for barberry removal, from burning to pulling.  On the Armstrong Preserve I either remove the entire plant (roots and all) or simply cut the plant at its base.  Cutting at the base leaves the roots, from which new shoots will grow.  With this approach subsequent cutting is necessary to finally kill the plant.  Cutting Japanese barberry at its base has some advantages over pulling the entire plant, namely causing less disturbance to the soil.  Around our vernal pool I decided to cut Japanese barberry instead of pulling it up because I wanted to reduce the amount of soil that ran into the water.  Likewise, in areas of well established Japanese stiltgrass, disturbing the soil to remove Japanese barberry might create an ideal seed bed for stiltgrass.

If cutting is your method of barberry managing, now is a great time to get out your tools.  Hit the plant before it leafs out to 1) prevent it from building up a tick-friendly microclimate and 2) prevent it from photosynthesizing (growing).  Cut every winter/spring until the plant gives up.  By continued cutting you are forcing the roots to resupply the shoots.  If you keep taking the shoots, the roots will shrink and eventually poop out.           

If you are facing Japanese barberry on your property, you are not alone.  It is so ubiquitous that eradication is not an option.  Instead we have to strategically manage the plant to prevent its spread, remove it from the most ecologically valuable sites and eradicate it where public health is most compromised (along paths and around schools).  The Invasive Project of Pound Ridge (TIPPR) is a recent initiative solely focused on managing invasive plants, including Japanese barberry.  TIPPR will be holding ongoing workshops and informational events to tackle the issue from a town-wide level.

This problem isn't going away.  Take up the fight, at least on your own property.