CATALOGUE OF DISEASES, continued. 



Hollyhock. RUST (Puccinia mahacearum). All parts of plant 

 show reddish brown pustules. 



Control. Eradicate mallow. Pick off diseased leaves and 

 burn. Spray every week with bordeaux mixture, 4-3-50. 

 Horse-Radish. WHITE MOLD <Cystopus candidus). -Deforming 

 and swelling of leaves and stems, with white powdery surface 

 growth. 



Control. Hardly important enough on the radish to neces- 

 sitate control. 



Hyacinthus. BLIGHT (Pseudomonas hyacinthi). Serious pest in 

 the Netherlands. Sap-tubes filled with yellow slime. 



Control. Destroy all affected plants. 



Hydrangea. LEAF-BLIGHT (Phyllosticta hydrangese). Leaf -spot 

 disease which become? serious at times. 



Control. Destroy diseased leaves as soon as noticed. 

 Iberis. CLUB-ROOT. See under Cabbage. 



Impatiens. MILDEW (Plasmopara obducens). Downy mildew of 

 the leaves. 



Control. Remove affected leaves and spray with bordeaux 

 mixture. 



Ipomoea. RUST (Coleosporium ipomcex). Common rust spotting 

 of leaves. 



Control. Destroy affected leaves. 

 MILDEW. See under Convolvulus. 



Iris. LEAF-BLIGHT (Botrytis galanthina). First the leaves and 

 flowers are much distorted and covered with black mold 

 growth; later the bulb may be destroyed. 



Control. Eradicate diseased plants and grow in new soiL 

 Juglans. LEAF-SPOT (Gnomonia leptostyla). Brown leaf -spot, 

 causing defoliation. 



Control. Collect and burn fallen leaves. Spray with 

 bordeaux mixture while leaves are young. 



Juniperus. CEDAR APPLES (Gymnosporangium spp.). Large or 

 small red and woody growth at tips of branches. Gelatinous 

 in wet weather. 



Control. Prune off affected parts. Keep apples, pears, 

 and hawthorns at a distance. 

 Kale. BLACK-ROT. See under Cabbage. 

 Kohlrabi. CLUB-ROOT. See under Cabbage. 



Laburnum. LEAF-SPOT (Peronospora cystisi). Leaves become 

 brown-spotted. Seedlings killed. 



Control. Spray with bordeaux mixture. 

 CONTAGIOUS CHLOROSIS. See under Abutilon. 

 Lariz. CANKER (Dasyscypha willkomii). Canker of trunk and 

 branches, usually around base of trunk. 



Control. Eradicate diseased parts, using tree surgery 

 methods. 



Laurus. WITCHES' BROOM (Exobasidium lauri). Branched out 

 growths, antler-like, 2 or 3 feet in length, springing from 

 the leaves. 



Control. Prune off affected parts. 



Lemon. BROWN-ROT (Pythiacystis citrophthora). White mold on 

 surface of fruit. 



Control. Not destructive in orchard. Add copper sulfate 

 to water when washing lemons to prevent infection of healthy 

 ones. 

 LEAF-DISEASES. Not well understood. Probably controllable 



by spraying. 



Lespedeza. MILDEW (Microsphsera diffusa). Powdery mildew of 

 leaves. 



Control. Dust with sulfur. 



Lettuce. DROP, or ROT (Sclerotinia libertiana). Base of steins or 

 leaves rots off, allowing leaves to drop. 



Control. Sterilize soil with steam before planting. 

 MILDEW. See under Cineraria,. 



Ligustrum. ANTHRACNOSE (Gleeosporium cingulatum). Affected 

 areas light brown either oblong on one side of the stem or 

 completely girdling it. 



Control. Destroy by burning affected plants. 



Lilium. LEAF-SPOT (Botrytis sp.). -Orange-brown or buff blotches 

 on leaves, stem and flowers of L. candidum. May be same as 

 Tulipa Mold, which see. 



Control. Eradicate diseased plants. 

 Lily-of-the- Valley. STEM-ROT. See under Paeonia. 

 Liriodendron. TWIG BLIGHT (Myxosporium longisporium). Kill- 

 ing twigs. 



Control. Prune off diseased twigs. 

 Lobelia. CANKER (Phoma devastatrix). Portions of the sterna 



covered with minute black dots. 



Control. Remove diseased plants. They never bloom. 

 Lonicera. CANKER ( Nectria cinnabarina) . Rough canker on limbs 

 covered with flesh-colored or red bodies. 



Control. Prune off or cut out all affected parts and cover 

 wounds with tar. 

 Lupinus. See under Pea. 



Lychnis. SMUT ( Ustilago violacea). Pollen-sacs filled with black 

 dust which escapes and discolors the flower. 



Control. Destroy the affected plants and use new soil. 

 Lycopersicum. See under Tomato. 

 Magnolia. LEAF-SPOT. See under Grapefruit. 

 Malva. RUST. See under Hollyhock. Same disease. 



CATALOGUE OF DISEASES, continued. 



Mangifera. BLACK BLIGHT (Dimerosporium mangiferum) . In- 

 tense black velvety patches on both surfaces of the leaves. 



Control. Spray with any good spray mixture. 

 Matthiola. CLUB-ROOT. See under Cabbage. 



Mentha. RUST (Puccinia menthse). A most destructive rust 

 disease. 



Control. None given. 



Mignonette. LEAF-SPOT (Cercospora resedss). First reddish 

 discoloration of leaves. Later small depressed spots with 

 brownish or yellowish margin. 



Control. Spraying with bordeaux mixture gives good 

 results. 

 Morus. LEAF-SPOT (Cercospora moricola). Not serious. 



LEAF-BLIGHT (Pseudomonas mori). Wilting and death of leaves. 

 Cankers girdle the twigs. 



Control. Prune off diseased parts and burn. 



Muscari. SMUT ( Urocystis colchici). Long black powdery streaks 

 on leaves. 



Control. Destroy affected plants by burning. Use new 

 soil. 



Mushroom. MOLD (Mycogone perniciosa). Mushrooms develop 

 abnormally as monstrous soft growths. These develop into 

 a moldy mass and putrify. 



Control. -Affected beds should be thoroughly cleaned and 

 sprayed with copper sulfate, one pound to fifty gallons of 

 water. 

 Muskmelon. DOWNY MILDEW. See under Cucumber. 



WILT. See under Cucurbita. 



Narcissus. LEAF-SPOT (Ramularia narcissi). Spots on leaves 

 and stem. 



Control. Burn diseased parts and spray with bordeaux 

 mixture. 

 Nasturtium. WHITE "RuST." (Cystopus candidus). See under 



Horse-Radish. 



Nectarine. YELLOWS, etc. See under Peach. 



Nerium. BLACK MOLD (Capnodium fcedum). Black velvety-like 

 growth on leaves. 



Control. Spray with bordeaux mixture. 



Nicotiana. ROOT-ROT (Thielavia basicola). Blackening and 

 rotting of the roots of seedling plants. 



Control. Steam sterilization of seed-beds. 

 MOSAIC or CALICO DISEASE. Enxymic disease. Mottling of 



leaf. Spread by touch. 



Oak. ANTHRACNOSE (Gnomonia veneta). Brown spotting on 

 under side of leaves, along veins. Brown pustules on spots. 

 Death of leaves and twigs. See under Arboriculture, Diseases 

 of Trees. 



Control. Collect and burn all diseased twigs and leaves. 

 Spray with bordeaux mixture frequently from time buds 

 swell. 



CEnothera. LEAF-GALLS (Synchytrium fulgens). Yellow swellings 

 on the leaves. 



Control. Destroy affected leaves. 

 Okra. See under Hibiscus. 



Olive. LIMB-GALL, or KNOT (Pseudomonas olex). Knots or galls 

 on the twigs and limbs. 



Control. Remove and burn affected limbs. 



Onion. MILDEW (Peronospora schleideniana). Causes a wilt or 

 blight of the leaves. 



Control. Spray with bordeaux mixture, 5-5-50, to which 

 has been added one gallon of resin sal-soda sticker. First 

 application when third leaf has developed, repeating every 

 ten days until harvest time. 



SMUT ( Urocystis cepulse). Black pustules on leaves and bulbs. 

 Seedlings may be killed outright. 



Control. Grow seed in new soil. Drill in with the seed 

 one hundred pounds of sulfur and fifty pounds of air-slaked 

 lime to the acre. 

 Opuntia. SPOT (Diplodia opuntix). Sometimes a serious pest 



of cactus. 



Orach. GALLS ( Urophlyctis pwZposcO.-^-Glassy swellings on 

 leaves, stems and flowers of Chenopodium and A triplex. 



Control. Burn affected plants. 



Orange. BLACK-MOLD (Capnodium citri). Black mold-like growth 

 on leaves and fruit. 



Control. Spray with any good fungicide. 



Orchids. LEAF-BLIGHT (Glomerella cincta). Leaf dies back from 

 the tip, turning brown. 



Control. Burn affected leaves. Spray frequently then 

 with bordeaux mixture. 



Ornithogalum. WARTS (Synchytrium niesii). Dirty white warts 

 on leaves, bounded by a dark line. 



Control. Burn diseased leaves. 



Pseonia. STEM-ROT and WILT (Sclerotinia pssonise). Gradual 

 wilting and dying of leaves caused by decay of stem at or 

 near surface of soil. 



Control. Spray the stems frequently with a strong fungi- 

 cide. Burn affected plants. 



Palms. LEAF-SPOT (Gleeosporium allescheri). May cause ultimate 

 death of leaves. 



Control. Frequent spraying with bordeaux mixture and 

 eradication of diseased leaves may prove beneficial. 



