White mold is a plant disease caused by the fungus Sclerotinia sclerotiorum. This pathogen is capable of infecting over 400 plant species. Flower garden favorites like zinnia, petunia, salvia, and snap dragon are highly susceptible to white mold. In the vegetable garden, tomatoes, green beans, lettuce and cabbage can all be infected. Removal of infected plants is a critical management strategy for white mold. The pathogen can survive up to eight years in specialized resting structures produced on infected plant material.

Plants infected with white mold often wilt and die. The lower stems of these plants will be tan and dry. If the humidity is high, white fluffy clumps of fungal growth may be seen on the stems. Gardeners may also see small, rough, black structures that look like seeds or peppercorns forming along stems or inside of them.

These are special resting structures, called sclerotia that are created by the fungus. Sclerotia can survive in the soil for up to 8 years. Each year the sclerotia produce tiny mushroom like structures that releases spores and starts new infections.

Gardeners that are seeing white mold in their gardens now, need to remove infected plants before sclerotia are dropped into the soil.

The entire plant should be removed as soon as possible. Infected plants can be composted if the pile heats up to a minimum temperature of 148 F. Alternatively infected plants can be deeply buried (6-12 inches below ground) in an area of the yard that will not be used for flowers or vegetables in the future like a mulched are around trees or shrubs.

Spiders are particularly common around homes and gardens during late summer and fall. Undoubtedly the most common types are the orb weaving spiders (family Araneidae). These spiders can be recognized from the large, circular, flat webs that they construct. They vary in size although many are moderate to large sized. Some species are very colorful. They typically have round, plump abdomens with relatively short stout legs.

There are two common groups of orb weaving spiders that people commonly encountered spiders in the genus Argiope and those belonging to the genus Araneus. Argiope spiders, also referred to garden spiders are large with a body length up to one inch long, and conspicuously colored yellow and black or silver, yellow and black. Their abdomen is more oval compared to most orb weavers.

Araneus species are typically moderate sized. They can be either brownish or colored brightly, especially orange or yellow. Their abdomens are generally more round, sometimes even somewhat triangular. Common species include barn (orbweaver) spider, cross orbweaver, shamrock orbweaver, and marbled orbweaver.

Fortunately despite their appearance, orb weaving spiders are not aggressive or dangerous to people and no control is necessary. In fact, orb weaving spiders are fascinating to observe and people should consider themselves fortunate to have an orb weaving spider in their garden or yard to watch.

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