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Plant NameTypeDescription 
Leaf spotIrisDiseaseLeaf spot is caused by a fungus which overwinters on dead leaves and other plant material. Spores develop in spring and infect leaves. Several cycles can occur in warm, wet weather, and the disease thrives on plants growing in acidic soils. Tiny brown spots emerge with water-soaked edges, later turning yellow. Near season's end after bloom, spots may multiply and run together. Severely infected leaves may die. Older spots reveal grayish centers with red-brown borders.
Bulb miteIrisInsectBulb mites are a typical pest of iris in Washington both in the gardens and in storage. Injured or bruised bulbs are the most susceptible to damage. Not only do mites destroy bulb tissue, but they also carry fungi and bacteria which often spur additional damage. Bulb mites are found in colonies. They are usually white with two brownish spots and measure a fraction of an inch in length (about 0.03 inch). Their oval shape and sluggish behavior can deceive the human eye into identifying them as eggs. They avoid the light, and hide under damaged or diseased tissue. Bulb mites also heavily affect hyacinths, lilies, and narcissus.