Garden Q&A: Transplanting an oak tree and, no, that’s not a murder hornet

The roots of a willow oak, and other nut-bearing trees, spread out sideways in the top 18 inches of soil.
- Original Credit: For The Baltimore Sun

I was surprised when I dug up this willow oak volunteer that was too close to the house. I thought oaks only had a tap root. This one has big roots but no little roots. Is it worth replanting? How can I help it?

This is a great example of root structure. Nut-bearing trees are known for their tap root when young, but then they mostly send out sideways roots in the top 18″ of soil, just like other trees and shrubs, though some trees have hairier roots. Mycorrhizae, natural soil fungi that attach in and on roots, play a crucial role in increasing root surface area so even roots with few fine roots like these can absorb more nutrients.


Yes, planting any oak is worthwhile, as they are a premier tree in the environment. For a successful transplant, follow these steps: Keep roots moist at all times. Pre-dig the planting hole for a quick transfer. Dig it wider than the roots, but not deeper. Keep soil attached to roots when possible. Transplant on an overcast, not breezy, day.

If there is a time lag, moisten roots and keep in shade or covered with plastic to prevent drying. Position your tree at the same depth it was growing — not deeper. Insure roots radiate out from the trunk. Backfill with original soil (a little added organic matter is okay). Firm soil around the roots, but don’t compact. Use excess soil to form a saucer to catch water. On a slope, only do this on the downhill side. Water deeply. Water during dry spells from spring through fall for two years. Protect from deer.


A huge black and yellow striped hornet was crawling on my window screen last night. It’s so big I think it may be the Murder Hornet that’s been in the news! It’s about 2″ long. I tried to swat it, but it got away. What should I do?

The Asian giant hornet is not in Maryland. It’s barely in the U.S. — only one dead one was found near Seattle. We’ve been flooded with photos of huge hornets, but they are all the queens of European hornets.

Now is the time when queens emerge, alone, from their winter rest and look for a cavity to start a new hive. They are startlingly big, for sure, and attracted to light at night. Always turn off outside lights at night to discourage them — and a slew of other unpleasant home pests — from being attracted to your home. If you see another huge hornet, look for black “drips” on the abdomen stripes, which means it is a European hornet.

Search the Home and Garden Information Center’s website for more identification tips. European hornets have a potent sting when disturbed.

University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at Click “Ask Maryland’s Gardening Experts” to send questions and photos.