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Sunday - October 21, 2007

From: Pflugerville, TX
Region: Select Region
Topic: Pruning, Trees
Title: Shaping of native hawthorns
Answered by: Barbara Medford

QUESTION:

I have three young hawthorns that were propagated from a nearby Blackland prairie stand. If I limb them up, will that encourage them to branch more near the top, or will it just ruin the form altogether? If I prune off lower branches, by what percentage can they be pruned without harming them? They have a spindly main trunk between 5 and 6 feet tall, and some of the lower lateral branches are approaching 1/2 inch in diameter. I've had them in the ground a couple of years. They resemble the hawthorn that is growing in the Wildflower Center's demonstration garden, which I understand is a "volunteer" hawthorn of unknown parentage. I don't know the genetic line of my hawthorns. I'd like the branching to become thicker near the top and have a less-gangly small tree.

ANSWER:

There are a LOT of hawthorns native to North America. Several are distributed naturally only in Texas; among these are Crataegus texana (Texas hawthorn), Crataegus turnerorum (Turner's hawthorn), and Crataegus viridis var. desertorum (desert hawthorn). Crataegus tracyi (Tracy's hawthorn) is found on the Edwards Plateau and west. These are all good possibilities for which hawthorn you have.

However, it really doesn't matter, in terms of pruning or shaping. One of the charms of the hawthorn is its rounded top and draping fronds of leaves and blooms but we can understand your not wanting it to become a bush. Certainly, lower branches may be pruned off as they emerge. Just be careful not to take off too much foliage at once, as those leaves are vital for nutrition to the plant. Wait a month or so to do this pruning, to allow the tree to get as deep in dormancy as possible. Your hawthorn could get to be up to 25 to 40 feet tall, so don't feel you have to do all the shaping at once. A tree that's only been in the ground two years is pretty young, so taking just a branch or two off this time would be a good idea. It won't necessarily contribute to the top getting fuller, but it will give that appearance as you develop a longer trunk.