21 June 2008 - 05:54, Tinman said:
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From PaulS, one of Mt D’s most adroit birders:

This morning at Mt. D. I observed 4 juv. WESTERN BLUEBIRDS from 7:30-7:40. The bluebirds, in spotted juv. plumage, first appeared near the utility box at the summit clearing and then proceeded to move around between eucalyptus trees and shrubs in the area of the upper Ravine. They occasionally called while perched. At 7:40, the group took off, circled once, then flew off to the west above the euc forest. This occurrence is unprecedented for the season and location. The 3 prior records of W. Bluebird at Mt. D. involved fly-overs in the late September/October time period (9/01, 10/02, 9/07). While this group of 4 may have recently fledged in the Presidio (assuming nesting has occurred there this year), I’m guessing they were post-nesting dispersers from south or east of SF.

Other observations of local interest:

• Olive-sided Flycatcher 2
• Pac.-slope Flycatcher 1 (called a few times in the “Bowl”)
• Steller’s Jay 1
• Br.-head. Cowbird 1 m., 1 f. (a few show up at Mt. D. around this time very year)
• Lesser Goldfinch 10+

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11 June 2008 - 09:24, Tinman said:
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The determined group of volunteers attacked primarily blackberry on The Ledge this month. This takes bravery and persistence, as the blackberry canes are equipped with thorns that will put your eye out or at least rip up your palms, arms, neck, and anything else they can reach.

Nonetheless, blackberry (Rubus discolor) is one of Mt D’s most acute invasive weed problems, so attack it we must. Left alone, a blackberry plant produces numerous canes from its central root crown—up to 525 canes per square meter in fact. The root crown can grow to eight inches in diameter and must be removed in order to take out the plant. (See more details here.)

Here is what one sees when staring into the heart of a thicket:

And here is what a root crown looks like when extracted:

This one didn’t set any records, but you can see how extracting it required a fair bit of effort.

We’re gradually pushing back the blackberry infestation from “good” areas such as The Ledge, the ridge that runs from the Mt D summit to the northwest. Along this ridge is an impressive Pacific reed grass community full of other native plant co-travelers. As we extend this managed area into the neglected areas, you can see a clear demarcation of Good vs Evil:

The work is painstaking because it must be done by hand in order not to cause more problems than we solve. Still, anyone walking through Adolph Sutro’s tree plantation on Mt D can see how much progress our efforts have produced.

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