The above title may sound redundant, but let me explain. Many plants go through transformations as they age. A familiar example may be our native red cedar, Juniperus virginiana. Young red cedars are quite prickly. Their needles are sharp, and they are uncomfortable to brush up against. They’re probably less attractive to deer and other herbivores than they would be if it weren’t for the prickles. When red cedars get to be more than a few years old, they start to replace their prickly foliage with needles that are flat, scale-like and much softer. You can see photos of red cedars, including the different leaf types at www.carolinanature.com/trees/juvi.html and http://dendro.cnre.vt.edu/dendrology/syllabus/factsheet.cfm?ID=97.
English ivy, Hedera helix, also undergoes a transformation as it matures. The leaves of young ivy are lobed—the shape is suggestive of a maple leaf. When mature, its leaves cialis soft tabs online lack lobes, and the shape is more like that of a teardrop. Unlike junipers, or humans for that matter, the transformation to the adult form doesn’t happen when ivy reaches a certain age. English ivy will remain in juvenile mode unless it climbs vertically. If allowed to climb and reach up out of the shade, it will flower and produce clusters of small black berries.
For an ecologically minded gardener like me, this is a very important revelation. English ivy is one of the worst scourges on our wild lands and forests. Birds spread the berries far and wide, and the resulting plants climb up and over our native vegetation, weighing it down and depriving it of light. English ivy is on many states’ noxious weed lists, and its sale and import has been banned in Oregon. It’s like kudzu, with a better press agent (I think it’s the “English” in its name—“English Ivy” brings to mind tea and crumpets and Mary Poppins, whereas “kudzu” sounds like a giant monster from a Japanese horror movie). Because ivy won’t make berries in its juvenile state, it can still be a benign component of our landscapes—as long as it’s not allowed to climb and undergo the transformation to reproductive maturity.
If you’ve got a bed of English ivy, I urge you to consider replacing it someday with plants that are more wildlife friendly (perhaps with our state flower, Carolina jessamine, or Virginia creeper underplanted with spring bulbs). If you want to keep your ivy, please don’t let it grow vertically—keep it from ascending trees, houses and fences to keep it from reproducing. All it takes is cutting it back to the ground a couple of times a year. Your trees (which won’t be smothered), your house (which won’t have its mortar or its paint damaged) and your neighbors (who won’t have as many young ivy seedlings to pull) will thank you.
More information on English ivy and its ecological threat can be found at www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds/weed-identification/english-ivy.aspx and www.nps.gov/plants/alien/pubs/midatlantic/hehe.htm, the latter of which has a link to a excellent article on controlling woody vines.
Donald McInnes has degrees in biology from Duke, Northwestern and Florida State. He has worked for Clemson Extension in Richland County for more than a decade, assisting thousands of consumers with landscape, garden, wildlife and pest control questions. He is also the owner of Southeastern Environmental Design, a landscape coaching, consulting and design service, and until recently chaired the City of Columbia’s Tree and Appearance Commission. If you’d like help with your landscape, he can be reached at seenvdes@aol.com.
