Fire blight can destroy orchards

Q. Our ornamental pear trees have fire blight – bad! If I cut them down, can I plant in the same spot? Help!

Kerri from Austintown

A. Ahh! The beautiful Callery pear (Pyrus calleryana) graces us with beautiful white blooms in early spring and turns a delightfully deep purple in fall. If you look closely, you’ll see it in nearly every block of homes in the Valley and nearly every yard in rural areas as well.

But do you know anything else about this plant other than it’s readily available and relatively cheap? Although beautiful, it has many negative characteristics.

For example, it’s native to China, is frequently damaged by storms due to weak crotch angles and it seems to get fire blight frequently, as Kerri noticed. Finally, it’s considered invasive: It’s showing up in natural areas.

As for the fire blight issue, it’s a dire one because it makes the tree unsightly and spreads to nearby crabapples and into local apple orchards. It shows up as dark brown to black leaves that do not fall from the tree. On apple trees, you can see a distinctive shepherd’s hook-style curl at the end of the stem. This is not as distinctive on callery pear to the average gardener in the home landscape. The more tell-tale sign is random browning of the ends of stems. This year, these “random leaf issues” are quite noticeable on callery pears.

Control can be achieved through proper pruning of the infected twigs (about 8 inches lower than the last sign of infection). But this is difficult to nearly impossible to prune on tall trees. Thus, removal and replacement may be the best option.

Some alternative trees to consider: Kousa dogwood (Cornus kousa) – Can take full to part sun, blooms later than native dogwood; serviceberry (Amelanchier arborea) – Full sun to part shade, early spring blooms, berries follow, native; Winter King green hawthorn (Crataegus viridis “Winter King”) – Full sun, vase shape, beautiful blooms, other thornless varieties available; Japanese lilac (Syringa reticulate) – Beautiful white/cream-blooming tree right now, full sun, heavy scent.

Eric Barrett is OSU Extension educator for agriculture and natural resources in Mahoning County. Call the office hotline at 330-533-5538 to submit your questions. Clinic hours are Mondays and Thursday from 9 a.m.-noon, through October.