alpine flowers at Grey Rock

Thursday, September 16, 2010

La Nina vs. El Nino

The Climate Prediction Center has posted an advisory for the return of La Nina.  Until the summer, we were under the influence of an El Nino effect.  These natural occurring cycles stem from ocean temperatures in the Nino 3.4 region of the equatorial Pacific from 165West to 120West.  When the waters in that area rise to .5C above the historical average, an El Nino pattern sets up.  If .5C below, La Nina. For the last month or so, the temps have cooled and thus the advisory. The dominant storm track will be from the North to Northwest and pick up some of the Polar Jet stream to make for wetter and cooler months ahead. The more the temperature in the ocean changes, the longer the effect.  NOAA will let us know as the pattern persists and the temperatures remain below average in the waters at the equator what will be in store for the Pacific Northwest area.

Saturday, September 4, 2010

Fall Webworm

The first time I noticed any amount of Fall Webworms was last year. This year, every madrone tree has at least one group of these on it. The Fall Webworm might be called a tent caterpillar, but it is truly Malacosoma disstria. The difference is that the webworm forms its nests at the tips of branches whereas the tent worm forms them in the crotches. They can be controlled by pruning or spraying the pathogen BT. How you are supposed to spray the tip of a branch 40 feet up is still open for discussion. There is a parasitic moth and fly that can do some damge, so I will hope my little ecosystem is produceing what it take. Although the caterpillars defoliate where they live, they seldom kill the tree. What if there were enough of them? Baltimore Orioles are hard on them, so I suppose the rest of that insect family would be. I have noticed an influx of Flickers lately...