Gardening Tips: Protect Against Sporotrichosis, Stop Apple Scab, and Prevent Strawberry Mold

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ILLUSTRATION: MICHAEL STORRING
When working with plants packed in sphagnum moss, wear gloves to protect yourself against wounds and avoid fungal infection.

You won’t find warning labels on purchased trees and
shrubs, but perhaps you should. The once-rare fungal
infection called sporotrichosis has become a major concern
to the nursery industry. Last year there were outbreaks of
this potentially serious disease in 14 states.

The fungus that causes sporotrichosis can contaminate
sphagnum moss and then enter the victim’s bloodstream via
small puncture wounds. Handling sharp-needled conifers is
thus riskier than handling deciduous plants; still, you
should wear gloves to protect against wounds when working
with any plants packed in sphagnum moss.

Symptoms typically begin a week or two after infection,
with red lesions on the skin of hands and arms. More
lesions follow, and these can have discharges or can
ulcerate. Sometimes there are severe complications.
Treatment is simple–oral dosages of potassium iodide;
unfortunately, many physicians do not diagnose
sporotrichosis accurately. If you have been planting trees
or shrubs (especially prickly ones) and have skin lesions
that don’t heal within a month, see your doctor and suggest
the possibility of this tree planter’s disease.

Research Briefs

Stopping apple scab. An Indian horticulturist reports that spraying a 5%
solution of urea, a soluble nitrogen fertilizer, on apple
trees late in the growing season (but before leaf fall) can
result in scab control comparable to that achieved by using
fungicides. Synthetic urea, made from petroleum, is
chemically identical to the urea in the animal urine, so
homemade manure tea may make a good (and non-oil-based)
substitute.

Stopping strawberry mold. Canadian researchers have found that clipping and removing
strawberry foliage can significantly reduce gray mold,
Botrytis cinerea, the following year (the mold
overwinters on dead leaves). It’s probably best to clip
leaves late in the fall so the root systems will have time
to store abundant food reserves.

Melon sweetness meters. USDA scientists have
invented a device to measure the sweetness of melons
without cutting them open. The machine measures how much
near-infrared light the fruit absorbs–the more, the
sweeter.

Stimulating sludge. Because municipal
sludge can be high in heavy metals and other hazardous
substances, most gardeners won’t risk applying it heavily
to food crops. Now, however, Arizona University researchers
have discovered that some sludge contains plant growth
stimulators (similar to natural cytokinins) that are
effective at very low application rates. No one
knows how they end up in sludge.

Reading and Products for Gardeners

The 366-page Fruit, Berry, and Nut Inventory (Seed Savers Exchange) describes over 4,000 cultivars currently
available from 248 nurseries in the U.S….Planning to try market gardening? Backyard Cash
Crops
(Homestead Design) is full of ideas on
growing and selling many kinds of specialty crops….An
excellent introduction to hobby greenhouses is given in
Greenhouses & Garden Rooms (Brooklyn Botanic Garden)….Deluxe fruit-picking baskets
are available from Friend Manufacturing Corporation.


Greg and Pat Williams raise most of their food on a
small farm and publish
HortIdeas, an e-newsletter on gardening research and products.

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