Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous Trees > Ribes > Leaves discolored white, yellow or pale green
Ribes > Leaves > Leaves discolored white, yellow or pale green
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Two-spotted spider mite
Tetranychus urticae
- White to yellow stippling on foliage; leaves can appear off-green
- Heavy infestations will cause leaves to turn white, yellow and ultimately grayish bronze
- Premature leaf drop may occur
- Webbing may be present, especially when heavily infested
- Mites usually appear in late June to August; they are more prevalent in hot, dry weather
- Adult spider mites are small(approximately 1/50 inch long) and are hard to see; they are yellow to dark red with dark spots (need magnification to see)
- More information on two-spotted spider mites
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Powdery mildew
Phyllactina guttata
- White, powdery spots or blotches on leaves
- Leaves and stems may be completely covered with white, powdery fungal growth
- Leaves may yellow and drop prematurely
- Young leaves and shoots may be curled and twisted
- Entire shrub may appear gray or discolored
- More information on powdery mildew
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Non-selective herbicide injury
(Round-up, Kleen-up, and other glyphosate products)
- Yellowing, wilting, browning leaves and eventual death of foliage and plants
- Damage usually appears first in new tissues
- Shrubs sprayed during the summer or fall may not have noticeable injury until the following season when leaves appear as stunted, narrow, strap-like, and chlorotic
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Plant Growth Regulator Herbicide Injury
(2,4-D, Dicamba, etc.)
- Leaves, stems, and petioles are twisted, distorted, and/or cupped
- Leaves may appear thick and leathery with parallel veins
- Youngest tissue at branch ends affected
- Distorted growth accompanied by or followed by leaves that turn brown or yellow
- More information on Plant Growth Regulator Herbicide Injury
