January 22, 2014

English Ivy


A row of poplars under a dull grey winter sky. All trunks are covered in a thick layer of English Ivy (Hedera helix).




English Ivy is a creeper that covers the forest floor or climbs into trees (and other objects). It attaches itself with small roots on the bark of the tree. This does not hinder the host tree, because the Ivy is not a parasitic plant, it only uses the tree as a prop. (To be sure, when the English Ivy is very tall, the tree risk breaking its branches under the weight, or not receiving enough sun rays on its leaves.)




At the end of autumn there is not much to eat for insects. When in November the English Ivy is in bloom with lots of small yellowish flowers rich in nectar, bees and hover-flies know where to go.





After flowering, berries develop. Now they are still green but dering winter they ripen and turn black. The branches that carry fruits and flowers do not climb or creep, they stand upright. The leaves on those fertile branches are lozenge-shaped.




The leaves on the other, creeping, branches have a different shape, they have three or five lobes with nerves of a lighter colour. In cold periods in winter they often turn reddish.


 

January 7, 2014

Lesser Duckweed


Lesser Duckweed (Lemna minor) is a small plant that lives in still waters. In summer it can cover the whole surface of a pond. In winter you can find it also but not in large quantity.





It floats on the water thanks to its round thallus with small air bags. It has a simple construction: a small round disk with some roots attached to it. In the tropics sometimes flowers develop, but in tamperate regions like France flowering seldom happens. To reproduce itself the plant makes more thalluses, and that's enough apparently.