When the Leaves Don't Fall in Fall

On the same topic as my recent post about why trees lose their leaves, there is an interesting article in today's Edmonton Journal about why the leaves aren't falling this year, and how that will affect the trees. As Dave mentioned in a comment on this blog, the nutrients the trees were storing in their leaves became "trapped" there during a sudden hard freeze, according to this article. When you combine those lost nutrients with the stress many trees are already experiencing from the dry summer, there is the potential for a lot of damage to trees this winter.

It's not too late to give your trees some extra water to help them through the winter, and we've luckily had some rain lately, with more in the forecast. A nice mulch of nutrient-rich compost or manure in the spring will also help them recover, according to the article. Personally, I'm still hoping that it's not too late for a little fall colour. I saw a cotoneaster hedge starting to show some beautiful reds today, so maybe there's still hope for the mountain ash that I usually count on.

1 comment:

  1. Hi Cassandra,

    I'm just back from a week in Winterpeg (where a sudden freeze also caught their trees unaware) to find our thaw. After reading your post, I took advantage of the sun and mild temperature to wander around the garden: very nice in an autumnal way.

    It's interesting how variable the response to the frost has been, even within a single family, e.g. the Rosaceae. The saskatoons are an interesting bronze, but that seems to be because every single leaf is dead. The chokeberry, however, seems to be putting on a normal fall splendor. The Scotch rose and the red-leaf rose look normal too. Can't really tell what is happening with the purple sandcherry, but I think it has gone the way of the saskatoon. The mayday clearly got clobbered, but the Nanking, Juliette, Carmen Jewel, and Evans cherries all seem to have suffered no more than 20% leaf mortality. Most of their leaves seem to be alive enough for the plant to retrieve the nutrients and maybe even show a bit of non-brown colour.

    I guess I'll be fertilizing next Spring, but I wonder what Dr Ieuan Evans would think of Janice Cooke's advice? In spite of the very low nutrient levels in composted manure, my plants have always shown an excellent growth response to it. But at $6 a bag, that would be a pretty expensive Spring boost if I tried to do all my woody plants. I wonder why judicious use of a slow release granular fertilizer wouldn't do just as well?


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