Answer: It's hard to say without seeing the leaves, what's effecting your firethorn (pyracantha). Pyracantha are susceptible to fire blight, but the symptoms are the young stems and leaves look like they were torched by fire. Sometimes really hot weatherwill cause leaf scorch and I believe you've already had a spell in Virginia. Other diseases such as scab and mildew could also be involved. As long as the new growth looks okay and the browning isn't spreading, then I wouldn't be too concerned. If it appears to be spreading, contact your local County Extension Agent (804-738-6191) and perhaps they can look at a leaf sample and help.
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