Monday, July 25, 2011

Nitrogen deficiency

Here is a maple where you can see that the leaves are yellowing between the veins showing it is lacking nitrogen. In the grass around the maple you can see the purple vetch a nitrogen fixing legume is doing exceedingly well. These two facts may be related. It seems like the purple vetch is doing better this year than either of the previous two years. In the previous years birdfoot trefoil seemed to be the dominant legume creating large mats but now in the square where the trefoil has been uncut for the third year now, the trefoil is losing out to the vetch. On the westside where this is only the second year without mowing the treefoil is still going strong.

Here is a link discussing the use of trefoil as a pasture crop. One thing they note is that while it is a perennial it needs to self seed if it is to become permanently established. I think we might have a situation where the trefoil needs a more disturbed and open location to get established than the vetch and that when young can't compete in the long term with the faster growing grasses and the weeds.


I was thrilled to see this monarch flitting about yesterday. I think they are so beautiful and know that their numbers are declining. This is the first I have seen this summer. I saw him in the long grass on the north side of the berm.

Japanese Beetle

A group of Japanese Beetles on a Glossy Buckthorn. Both the plant and the insects are invasive species. The Japanese Beetles are a large slow beetle that like to hang out in groups on the top of leaves. They spend their grub stage in lawns eating grass roots but here you see them too busy mating to care about predators. They must not taste very good to birds as they are easily spotted with their shiny armour and their habit of hanging out on the top of a leaf in broad daylight munching away. Here you see the lace like evidence of them eating the leaves of the bush. They are a bit of a generalist in what they eat but I have noticed them to be fond of raspberries.