Sunday, December 25, 2011

Monterey pine and coast live oak ~ 12/25/11 ~ Jacks Peak

coast live oak
Quercus agrifolia var. agrifolia

This post is for Cindy of Dipper Ranch based on her recent comment. I wish I had better pictures of how the ends look chewed. I noticed before at Jacks Peak that tips of Monterey Pine litter the trail. This is the first time I noticed tips of coast live oak also on the trail. To me they look like they've been chewed off, but I don't really know. We haven't had any wind storms lately, so I don't think that's the reason. It just seems a bit unusual to find tips of trees on the forest floor. Maybe a pruning-happy tree squirrel did this? Anyone have any ideas as to why this happens?


randomtruth said...

Rodents, such as gray squirrels and woodrats, definitely nip off tree tips, and then forage them from the ground for their nests and food caches. I just caught a dusky-footed woodrat on a cam trap collecting live oak twigs with fresh leaves. That said, I dunno about pine, and those look pretty large, so I'm not sure who your culprit might be. Maybe a gray squirrel. It's probably something brilliant - e.g., they've learned that pruning the trees increases tip branching and thus cone and acorn production, or like... :)

Cindy said...

My guess is squirrel also, especially since I see a loose scale from a cone under the pine branch tip. Mark Elbroch says squirrels cut off the tips of branches to eat acorns, seed cones, buds, even smaller male cones. Look for a smooth angled cut at the end (think about how their bottom and top teeth come together) or on larger branches it will be a stepped cut from several bites to cut through. They should be starting their breeding season soon and may be making their dreys (nests) using branch tips as some of the building material. On the other hand it could be wind-whipped tips but the cut end probably won't look the same. I am trying to post some other animal sign on vegetation but haven't been able to get Blogger to work today. Interesting what randomtruth says about woodrats since I always see leafless twigs in their nests but that doesn't mean they don't forage or collect branch tips.

randomtruth said...

Sorry - I was a bit unclear - the woodrats collect the fresh oak twigs with leaves and buds for food, not for midden building materials. So you wouldn't see them on the nest, but inside in one of the caches.

Cindy said...

ohh, where do woodrats keep their cache? Inside the stick nest? Katie: I posted the photos of animal sign on vegetation here: . This is fun noticing similar yet somewhat different things going on in our natural areas at about the same time.

Katie (Nature ID) said...

This was a fun post thanks to your comments. The next time I'm up at Jacks Peak I'll have to keep a look out for the 2 tree squirrels in our area, the western/CA gray and the eastern fox. For as natural as the place looks, there are a ton of fancy estates up on the hill, which makes me think the eastern fox is up there like at home in town. Too bad I can't get a cam trap up on the branches to see what's really going on.

Ken, way back when I showed your fabulous woodrat pics to my husband, and he also suggested perhaps woodrats were the cause for the clippings. I like anthropomorphic comparisons; we could actually learn quite a bit from non-human animals. So, um, when are you going to set up a cam trap inside a woodrat midden? Is that possible, without disturbing the family too much?

Cindy, I realized too late my brief description above that piqued your interest didn't adequately describe what I was seeing. I'm guessing Ken will have some ideas to your new post. Your link was interesting - is that a database co. that CDFG is using?

randomtruth said...

Sorry - missed your follow-up questions. Yes, the food caches are inside their houses, like little pantries. They fill them with all sorts of leaves, nuts and fruits.

Putting a cam in a midden would be fun. But setting them right outside is pretty much just as good, because you can catch the woodies foraging, other tenants coming and going, and even predators sniffing around. I'm working on such a survey right now, and am getting all sorts of terrific shots. :)