Host Plants - Westcott's Plant Disease - page 665

Black Line, Girdle. Graft incompatibility.
Dieback. Boron deficiency, OR.
Erinose. Leaf galls from blister mites.
Leaf Scorch, Sunscald. NJ. OR, WA.
Little Leaf. Zinc deficiency, CA. Probably also
causes Rosette.
Shrivel, Witches' Broom, Yellows. Cause
unknown.
P HYTOPLASMA , Witches' Broom, GA, IL, IN, IA,
OH.
P OWDERY M ILDEW . Phyllactinia corylea, IN, OH,
OR; Microsphaera

V IRUS , Mosaic and Stunting. Turnip Virus, Brazil.
W HITE R UST ; White Blister. Albugo candida,MN.

Water-Elm (Planera)

R OT , Wood. Daedalea ambigua, SC;

Ganoderma lucidum.

Water-Horehound (Lycopus)

alni, widespread;

Erysiphe polygoni, CA.
R OT , Collar. Phytophthora cactorum, CA;
P. cinnamomi, MD to AL, LA.
R OT , Heart. Fomes igniarius and F. everhartii,
widespread;

G ALL , Leaf. Synchytrium cellulare, WI.
L EAF S POT . Ascochyta lophanthi, MA, WI;
Cercospora lycopi, LA; Phyllosticta
decidua, IA, OK, WI; Septoria lycopi, WI.
R UST . Puccinia angustata (0, I), ME to MD, KS,
ND; II, III on grasses.

Polyporus sulphureus,

widespread.
R OT , Root. Armillaria mellea, cosmopolitan;
Phymatotrichum omnivorum, TX;

Water-Hyacinths (Eichhornia)

Cylindrocladium sp., TN.
R OT , Wood. Fomes conchatus; Polyporus spp.;
Poria spp.; Schizophyllum commune, cos-
mopolitan;

B LIGHT . Aquathanatephorus pendulus

Daedalea confragosa; D. ( Rhizoctonia stage), LA.

L EAF S POT . Cercospora piaropi, FL.
R OT , Root

quercina, widespread.
S CAB . Cladosporium sp., MD, MN.
V IRUS . Brooming Disease, DC, GA, MD, NY.
Bacterial blight is the most serious disease of
walnuts on the Pacific Coast, requiring several
sprays. A toxin, juglone, has been considered
injurious to many shrubs growing in the vicinity
of black walnut roots; the toxin also causes vas-
cular wilt-like symptoms in eggplant and tomato
in home gardens.

and Crown. Mycoleptodiscus

terrestris, FL.

Water-Lily (Nymphaea)

L EAF S POT . Alternaria sp., TX; Cercospora
exotica, IL; C. nymphaeacea, scattered ME
to TX, CA; Helicoceras nymphaerum, MD,
NJ, NY; Mycosphaerella pontederiae, MI,
VA; Ovularia nymphaearum, MD, NY,
WA; Phyllosticta fatiscens, VT;
Dichotomophthoropsis nymphaerum, MN;
Sclerotium sp., MN.
R OT , Leaf and Stem. Pythium spp., MA, NY, WI.
S MUT , White. Entyloma nymphaeae, MA to VA,
OK, WI.

Water-Cress (Nasturtium Officinale)

D AMPING -O FF . Rhizoctonia solani, TX.
L EAF S POT . Cercospora nasturtii, CA, CT, FL,
IN, NH, TX, WI.
R OT , Root. Pythium debaryanum, TX;
Sporgospora subterranea f. sp. nasturtii,
FL, PA; Phytophthora cryptogea, and stem,
FL.
R UST . Puccinia aristidae, AZ, CO, TX.
V IRUS . Western Aster Yellows Phytoplasma,
HI.

Water-Lily, Yellow Pond-Lily (Nuphar)

L EAF S POT . Dichotomophthoropsis

nymphaerum, MN.