Heteranthera multiflora (mud plantain) Pontederiaceae (3 3 3 3) 780 -- pale purple or white; spike elongating well out of spathe

Heteranthera reniformis (mud plantain) Pontederiaceae (3 3 3 3) 779 -- fls pale blue or lavender; lvs roundish; spike not out of spathe Heterotheca subaxillaris (camphor weed) Asteraceae/Astereae 531 -- Heuchera americana (common alum root) Saxifragaceae (5 5 5 2+ peri) 215 -- greenish, white or pink fls; lvs often white-mottled

Heuchera villosa (hairy alum root) Saxifragaceae (5 5 5 2+ peri) 215 -- very hairy plant Hibiscus moscheutos (swamp rose mallow) Malvaceae (5 5 5 1 hypo) 132

Hibiscus syriacus (rose of sharon mallow) Malvaceae (5 5 5 1 hypo) 132 -- stem woody; various colors; AL/AT lvs us 3-lobed, ovate in outline

Hibiscus trionum (flower of an hour mallow) Malvaceae (5 5 5 1 hypo) 133 -- pale yellow w dk center; AD trif; fls last only a few hrs Hieracium aurantiacum (orange hawkweed) -- red-orange fls

Hieracium caespitosum (field hawkweed) 592 -- head 4 or more; green stem & lvs hairy; BE lance

Hieracium flagellare 592 -- heads us. 2 to 4 (sometimes 1); lvs green beneath; stem stout

Hieracium floribundum (pale hawkweed) 592 -- smlr to H. c. but upper lf nrly smth; stem & lvs w whitish bloom

Hieracium gronovii (hairy hawkweed) 594 -- many fl'ed; w/ hairy BE basal lvs; AE stem lvs mostly toward bottom

Hieracium kalmii (Canada hawkweed) -- no basal rosette at flowering time; AT sharply toothed, upper somewhat clasping; fl head 1" wide

Hieracium lachenalii (common hawkweed) 593 -- BT basal rosette; fl base dk hairy; dandelion-like

Hieracium murorum (hawkweed) 593 -- 1-1.5" fls; basal rosette

Hieracium paniculatum (panicled hawkweed) 595 -- many fl'ed infl; slender, drooping floweringbranches; fls 1/2" wide; AT sl toothed, nippled; dry woods

Hieracium pilosella (mouse ear hawkweed) -- heads us solitary; lvs white-woolly beneath; stem slender

Hieracium piloselloides (smooth hawkweed) -- similar to H.k. but stem & lvs nearly smooth; lvs glaucous

Hieracium robinsonii (Robinson's hawkweed) 593 --

Hieracium saubadum (hawkweed) 593 --

Hieracium scabrum (rough hawkweed) -- mny fl'ed panicle; us. w/out basal lvs; upper stem dnsly hry & AT leafy to fl cluster

Hieracium sp. (hawkweed) Asteraceae/Lactuceae --

Hieracium venosum (rattlesnake hawkweed) -- purple-veined lvs Hierochloe odorata (sweet grass) Poaceae 713 --

Hippuris vulgaris (mare's tail) Hippuridaceae (0 0 1 1 epig) 431 -- Holcus lanatus (velvet grass) Poaceae 712 -- gray green, velvety lvs; infl wispy, pale green to purple; grows in tufts

Holcus mollis Poaceae 712 -- Holosteum umbellatum Caryophyllaceae (5 5 3-10 3) 101 --

Honckenya peploides Caryophyllaceae (5 5 10 3-5) 101 -- Hordeum brachyantherum (meadow barley grass) 729

Hordeum geniculatum (Mediterranean barley grass) 729

Hordeum jubatum (squirrel-tail grass or foxtail barley grass) 729

Hordeum leporinum (barley grass) 729

Hordeum murinum (barley grass) 729

Hordeum sp. (barley grass) Poaceae

Hordeum vulgare (barley grass) 729 -- very long bristles much overtopping infl; infl stays upright Hosta lancifolia Liliaceae (3 3 6 3) 788

Hosta ventricosa Liliaceae (3 3 6 3) 788 -- Hottonia inflata (featherfoil) Primulaceae ((5) 5 5 1) 203 -- Hudsonia ericoides (golden heather) Cistaceae (5 5 8-30 1or0) 140 -- plant greenish; lvs needle-like

Hudsonia tomentosa (beach heather) Cistaceae (5 5 8-30 1or0) 140 -- plant grayish-white hairy; lvs scalelike, bluntish, pressed to stem Humulus japonicus (Japanese hops) Cannabaceae (0 5 5 1 unisex) 070 -- lvs 5-9 lobed, hairy; petiole hairy

Humulus lupulus (common hops) Cannabaceae (0 5 5 1 unisex) 070 -- lvs 3 lobed, not hairy Hybanthus concolor (green violet) Violaceae (5 5 5 1) 142 -- greenish-white fl hanging from axils; AE ellip; rich woods Hydrangea arborescens (American hydrangea) Hydrangeaceae (4-5 4-5 8or10 2-4) 205-- infl flt-tpped/brdly convex; OT rnd, shrply tthed, ptd; native

Hydrangea paniculata (panicled hydrangea) Hydrangeaceae (4-5 4-5 8or10 2-4) 205 -- infl pyramidal or ovoid; cult & rarely escaped

Hydrangea quercifolia (oak-leaved hydrangea) Hydrangeaceae (4-5 4-5 8or10 2-4) 205 -- Hydrangaceae (hydrangea) -- Hydrangea, Philadelphus

Hydrastis canadensis (golden seal) Ranunculaceae (0 3 N N) 061 -- greenish-white stamens; AT/AL lvs 2 stem & 1 basal Hydrocharitaceae (frog's bit) -- Egeria, Elodea, Limnobium, Vallisneria Hydrocotyle americana (marsh pennywort) Apiaceae (5 5 5 2) 344 -- lvs scalloped

Hydrocotyle sibthorpioides (lawn pennywort) Apiaceae (5 5 5 2) 344 -- lvs small

Hydrocotyle umbellata (water pennywort) Apiaceae (5 5 5 2) 344 -- lvs more deeply indented

Hydrocotyle verticillata (whorled pennywort) Apiaceae (5 5 5 2) 344 -- lvs sl. indented Hydrophyllum appendiculatum (biennial water leaf) Hydrophyllaceae ((5) (5) 5 1 hypo) 394 -- stamens exserted only 1-3mm

Hydrophyllum canadense (maple-leaved water leaf) Hydrophyllaceae ((5) (5) 5 1 hypo) 394 -- stamens exserted 3-6mm

Hydrophyllum macrophyllum (large-leaved water leaf) Hydrophyllaceae ((5) (5) 5 1 hypo) 393 -- hairs 1-2mm

Hydrophyllum virginianum (Virginia water leaf) Hydrophyllaceae ((5) (5) 5 1 hypo) 393 -- hairs less than .5mm Hyoscyamus niger (black hyoscyamus) Solanaceae ((5) (5) 5 2 hypo) 383 -- Hypericum adpressum (appressed st. johnswort) Clusiaceae (4-5 4-5 N 2-5)127

Hypericum boreale (northern st. johnswort) Clusiaceae (4-5 4-5 N 3)129

Hypericum canadense (Canada st. johnswort) Clusiaceae (4-5 4-5 N 3)129 -- lvs lanceolate

Hypericum densiflorum (dense-flowered st. johnswort) Clusiaceae (4-5 4-5 N 3)126 -- shrub

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