Removing Invasive Plants from Stanley Park

English Ivy, Blackberry, Lamium, Periwinkle : Volunteers Needed

     Home    English Ivy    Lamium and Periwinkle    Blackberry    Obstruction     

Yellow Lamium , Lesser Periwinkle, English Laurel and Holly

Yellow Lamium - all cleared

Lamium (or Yellow Archangel, Lamium galeobdolon) is used by gardeners as ground cover because it spreads so well - exactly the characteristic that makes it so dangerous in the wild. Lamium is very hard to remove and harder to prevent re-growth. It grows from a small ball below the surface that is firmly anchored by many tiny roots. You must work your fingers down below each plant's root-ball before pulling. Plants spread with very fine horizontal stems above-ground that root many feet away.

When the leaves are damp they are very difficult to tell apart from buttercups because the light reflecting from the buttercup's indents gives the same impression as the lamium's variegation. The April flowers are a dead give away.

Stanley Park invasive plants - lamium..Stanley Park invasive plants - lamium mat

Where at all possible it is easiest to use a sharp turf shovel to remove the top inch of soil completely - getting all the root-balls and horizontal stems at once. I borrowed one from near-by road crews who kept their shovels nicely sharpened. Six years after clearing the spot at Hollow Tree, new plants are still showing up - despite regular checking. These plants must be coming from seeds that have remained viable for many years.You may want to try using a stiff garden rake to both loosen the soil and dislodge the root-balls. Then sift the soil to remove the plants. I would expect that method requires much greater follow-up work.

Do NOT throw pullings onto any compost pile. They do not die. They colonize the whole pile. It is best if they go into the garbage. The only alternative is to 'rot' them in place covered in plastic - a process with its own problems.

The cultivated gardens adjacent to the wild west of Stanley Park are rapidly being taken over by this plant. Starting at the park boundary , the plant beds covered in Lamium are getting closer and closer with every year. And each plant bed quickly progresses from a few weeds to being completely over-run. Yet the gardeners do absolutely nothing. NOTHING.

Stanley Park invasive plants - sites cleared of Yellow Lamium and Periwinkle

Lesser Periwinkle

Periwinkle (Vinca minor), another gardeners' ground cover, is much easier to deal with. If there are no other plant species mixed in, then the periwinkle can be easily pulled up by clumps. Doing this in the summer dry period allows any remaining plants to die from dessication in the disturbed soil. If there are other plants among the Periwinkle then it is better to wait for the winter die-back. Pulling in wet weather will mean that some plants remain viable, but they can be easily found with a few repeat visits. Pullings will compost if simply left in a pile and turned a few times.

Stanley Park Invasive Plants - periwinkle flower..Stanley Park invasive plants - periwinkle leaves

English Laurel - all necessary plants now cleared

English Larel (Prunus laurocerasus) is a foreign plant but not invasive - at least not in Stanley Park. I have spotted nine individual plants in the wild west of the park. Four were full grown at about six or seven feet tall in different areas. One has a trunk thick enough to be a tree. Yet only one of the small plants was close enough to possibly be an offspring. The others were widely dispersed. The remaining very large 'tree' does not flower, so I feel it is safe to leave.

Stanley Park Invasive Plants - English Laurel leaves, prunus laurocerasus..Stanley Park invasive plants - English Laurel, prunus laurocerasus

In the wild these plants are not the bushy hedges you see in town. They have a limited number of long stems. The alternating leaves twist to all face flat upward. The leave are thick and glossy. You can tell the difference from Salal by Salal leaves' slighly wavy edge. Lots of websites warn about the leaves, stem and roots of Laurel plants causing rashes when touched. I don't know how serious that all is, considering the widespread use of the plant as garden hedges. I have pulled up the small plants by hand, and had leaves brush my face, without any effects.

For small to medium size plants, the roots radiate just under the soil so no gloves or tools are necessary. Just grasp the stem and pull. It takes about a minute. For larger plants there will be one thick root often running sideways. It is easy to cut through with the keyhole saw used when clearing Blackberries.

Stanley Park invasive plants - sites cleared of English Laurel

Holly

There are tons of Holly plants growing through the wild west of the park. But they never seem healthy or vigorous. They never form trees. So I conclude they are not invasive - they don't out-compete other native plants. When prioritizing work, their removal should rank far lower than the priority to extend the areas cleared of Ivy and Blackberries.




     Home    English Ivy    Lamium and Periwinkle    Blackberry    Obstruction