Spring has sprung and gardeners are digging in. Got questions as you carry on? Get answers from Ask an Expert, an online question-and-answer tool from Oregon State University’s Extension Service. OSU Extension faculty and Master Gardeners reply to queries within two business days, usually less. To ask a question, simply go to the OSU Extension website and type in a question and the county where you live. Here are some questions asked by other gardeners. What’s yours?

What type of pine tree is this?

Which kind of pine tree is this?OSU Extension Service

Q: At a Don Pedro’s in Beaverton there’s a pine tree that doesn’t lose its cones; it looks like they are grafted on it. I cut a limb as a souvenir, plus it looks awesome as an art piece. – Multnomah County

A: There are only a few species of pines that have cones attached as you see them. As you are aware, most pine cones originate farther toward the ends of the branches.

Without seeing the tree or the needles, I suggest that this is either a Monterey pine (Pinus radiate) or a knobcone pine (Pinus attenuata). The knobcone pine generally holds its cones tightly closed, until the high temperatures of a forest fire open them up. I think it is unlikely that Don Pedro’s has had such a fire recently. Read more about this tree here.

So, let’s consider the Monterey pine. It has the same way of attaching the cones to the trunk or large branches. They hold onto the tree for many years, even becoming embedded in the bark. The difference is that they do not need the heat of fire to open their cones up, as we see here. Read more about this species here. These two trees can hybridize with similar species and, though native to California, are adapted here. – Claudia Groth, OSU Extension Master Gardener

What’s the best way to get weeds out of flower beds?

Is there a suitable pre-emergent product to "eliminate" weeds sprouting in flower beds? I am concerned that chemicals will also kill desired plants; tulips, perennials and annual plantings. Ð Lane County For use with Ask an Experts column.

Q: Is there a suitable pre-emergent product to “eliminate” weeds sprouting in flower beds? I am concerned that chemicals will also kill desired plants; tulips, perennials and annual plantings. – Lane County

A: I cannot recommend any herbicide for a mixed flower bed that is safe. Most are designed for woody plant areas or lawns. Weeding and then mulching work pretty well, actually. – Pat Patterson, OSU Extension Master Gardener

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