Q. I've had a nice, ornamental woody plant that leafed out OK this spring, and now the leaves wilted and turned brown. It was just after a big rain. Will it be OK, or is it probably dead?
A. It is probably dead. That is a typical symptom of a bush or tree dying from a root rot or similar vascular disease; it often occurs in a wet spring, which we have had this year. While our actual rainfall total might not be that large (e.g. compared to 2008 and 2009), the soil has been pretty much quite wet since thawing out. If one then gets a heavy rain it can push some plants over the edge.
Some plants are more prone to getting "wet feet" than others. Cherry trees are notorious for this, and we're getting reports of weeping cherries dying this spring. One wants to avoid wet areas like low spots or near gutter or similar discharge areas with sensitive trees or shrubs. Putting them on a berm or raised bed can compensate. Also, once a plant has died in a location, avoid replanting the same plant back to that spot, no matter how much you liked it. That disease organism is lurking in the soil, and there is no guaranteed effective way to rid the soil of that inoculum.
You might wait a month to see if it comes back. If it hasn't by then and the stems are brittle, remove it. If you want to replace it, it will be easier to establish and care for a newly planted woody plant in the fall.
Q. I have a Bradford pear tree, and some of the branches are getting brown at the end and drying up, kind of curving. Someone told me it has a disease. Is that true, and what can I do to stop it?
A. Bradford-type pear trees are now getting fire blight, a disease they used to be resistant to. The disease has long plagued apples and pears, such that many cultivars of those bearing fruit are rated for resistance to this disease (see next question). The brown branch symptom you are referring to has been coined as having a "shepherd's crook" shape. Larger branches can also die, and even major branches, at which time oozing, black-ish cankers often occur.
Controlling fire blight is challenging. The disease is more problematic in cool, wet springs, and it was really bad in 2014. With warmer weather coming, we're hoping it won't be as bad this year, as it hasn't been as prevalent so far. Pruning out afflicted branches is helpful, but must be done carefully. Always cut about 1 foot below any affected tissue and sterilize the pruning implement with rubbing alcohol between EACH cut. This means if pruning is impractical and the damage is not severe (e.g. a large tree), then do nothing.
Spraying to control it should be timed to two critical periods of growth. A dormant growth phase (all leaves off) application of copper sulfate should be made, with late February or early March being ideal. At flowering, streptomycin should be applied; if two applications can be made during flowering, that is even better. Streptomycin is not commonly available, but can be found. Sometimes it is called "Fire Blight Spray." Consider ordering from a catalog if you can't find it at your favorite retailer.
Q. I wanted to plant a pear tree and was wondering what varieties extension was recommending?
A. We have a nice, short list of most commonly planted fruit trees available in our Master Gardener Fruit Production Chapter, which is free and available on the Web. It recommends these five, noting that they are resistant to fire blight: Harrow Delight, Kieffer, Moonglow, Seckel and Starking Delicious. For great information on fruit growing, please see this publication at extension.missouri.edu/p/mg6.
The local Master Gardener hotline is staffed from 12:30-4:30 p.m. Tuesday and Friday afternoons; call 573-634-2824 then or anytime to leave a message. The Central Missouri Master Gardeners are a volunteer group of 191 members, 122 of whom are Cole County residents, who maintain 11 beautification sites in Cole County. Master Gardeners must complete a basic training program of at least 30 hours of horticultural training including landscaping, lawns, vegetables, flowers and fruits, as well as 30 hours of volunteer service. Have a gardening question of your own?
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