Atlas of the Flora of New England

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Genera - J

Jacobaea
Jasione
Juglans
Juncus
Juniperus
Justicia


JACOBAEA (Family: Asteraceae)


JACOBAEA VULGARIS Gaertner - Stinking Willie. 2n = 40.


Wet pastures, roadsides. From Eurasia, northern Africa. [SENECIO JACOBAEA Linnaeus]



JASIONE (Family: Campanulaceae)


JASIONE MONTANA Linnaeus - Sheep’s-bit. 2n = 12.


Roadsides, sandy banks, fields, waste places, often in sandy soil. From Eurasia.



JUGLANS (Family: Juglandaceae)


JUGLANS AILANTIFOLIA Carrière - Japanese Walnut. 2n = 32.


Thickets, roadsides. From Japan, Sakhalin, Russia. [J. MANDSHURICA Maximowicz var. SACHALINENSIS (Miyabe & Kudo) Kitamura; J. SIEBOLDIANA Maximowicz]


Juglans cinerea Linnaeus - Butternut. 2n = 32.


Roadsides, rich woods, river terraces and valleys, rocky slopes.


Juglans nigra Linnaeus - Black Walnut. 2n = 32.


Rich woods.



JUNCUS (Family: Juncaceae)


Juncus alpinoarticulatus Chaix - Alpine Rush. 2n = 40.


Shores, meadows, usually basic. [J. alpinus Villars; J. alpinus var. fuscescens Fernald; J. alpinus var. rariflorus Hartmann]


Juncus anthelatus (Wiegand) R.E. Brooks - . 2n = 80.


Moist sandy or clay soils. [J. tenuis Willdenow var. anthelatus Wiegand]


Juncus articulatus Linnaeus - . 2n = (40), 80.


Shores, springy spots, ditches. [J. articulatus var. obtusatus Engelmann]


Juncus balticus Willdenow subsp. littoralis (Engelmann) Snogerup - Wire Rush. 2n = ?


Sandy shores, sphagnous meadows. [J. arcticus Willdenow var. balticus (Willdenow) Trautvetter]


Juncus brachycarpus Engelmann - . 2n = 44.


Salt marshes, ocean beaches.


Juncus brachycephalus (Engelmann) Buchenau - . 2n = 80.


Basic shores, marshes, meadows, swamps.


Juncus bufonius Linnaeus - Toad Rush. 2n = 80, 106, 108.


Shores, salt marshes, roadsides, moist to wet borrow pits. [J. bufonius var. halophilus Buchenau & Fernald]


Juncus canadensis J. Gay ex Laharpe - . 2n = 80.


Shores, swamps, marshes, meadows. [J. canadensis var. sparsiflorus Fernald]


JUNCUS COMPRESSUS Jacquin - . 2n = 44.


Disturbed wet ground, especially ditches, roadsides, frequently saline or basic soils. From Europe.


Juncus debilis A. Gray - . 2n = ?.


Ditches, pools, shores.


Juncus dichotomus Elliott - . 2n = ca. 80.


Sandy or sphagnous shores, salt marsh borders. [J. platyphyllus (Wiegand) Fernald; J. tenuis Willdenow var. dichotomus (Elliott) Alph. Wood]


JUNCUS DIFFUSISSIMUS Buckley - . 2n = ?


Waste places, shores, typically in sandy, wet soil. Probably from South America.


Juncus dudleyi Wiegand - . 2n = 42, 80, ca. 84.


Shores, boggy meadows, in basic soils. [J. tenuis Willdenow var. dudleyi (Wiegand) F.J. Hermann]


Juncus effusus Linnaeus - Tufted Rush. 2n = (5), 40, 42.


Marshy ground, low spots. [J. effusus var. compactus misapplied; J. effusus var. conglomeratus (Linnaeus) Engelmann invalid name; J. effusus var. costulatus Fernald; J. effusus var. decipiens Buchenau; J. effusus var. pylaei (Laharpe) Fernald & Wiegand; J. effusus subsp. solutus (Fernald & Wiegand) H¨met-Ahti; J. effusus var. solutus Fernald & Wiegand; J. conglomeratus Linnaeus; J. pylaei Laharpe]


JUNCUS ENSIFOLIUS Wikström var. ENSIFOLIUS - . 2n = 40.


Disturbed wet ground, especially ditches, roadsides. From farther west.


Juncus filiformis Linnaeus - . 2n = (40), (70), (80), 84.


Shores, swamps, bogs, alpine meadows.


Juncus gerardii Loiseleur-Deslongchamps - Black Grass. 2n = 80, 84.


Salt marshes. [J. gerardii var. pedicellatus Fernald]


Juncus greenei Oakes & Tuckerman - . 2n = 80.


Dry, open places, usually well-drained, sandy soil. In pine lands near lake shores, dunes.


JUNCUS INFLEXUS Linnaeus - . 2n = 20, (38), 40, (80).


Meadows, damp roadsides. From Eurasia and northern Africa.


Juncus marginatus Rostkovius - Grass Rush. 2n = (38), 40.


Sandy pond margins, wet meadows. [J. biflorus Elliott]


Juncus militaris Bigelow - Bayonet Rush. 2n = ?.


Shallow water of ponds and streams with sandy, gravelly or sphagnous margins.


Juncus nodosus Linnaeus - . 2n = 40.


Shores, marshes, meadows, swamps, especially basic soils.


Juncus pelocarpus E. Meyer - . 2n = 40.


Sandy shores, marshes, ditches.


Juncus pervetus Fernald - . 2n = ?


Salt marsh borders. [J. SUBNODULOSUS Schrank misapplied] This taxon is possibly of hybrid origin. Only historical collections with aborted seeds are known.


Juncus pondii Alph. Wood - . 2n = 40.


Tidal mud flats, salt marsh borders, ditches, shores, meadows. [J. acuminatus Michaux -- invalid name]


Juncus secundus P. Beauvois ex Poiret - . 2n = ca. 80.


Ledges, dry, open, sterile soils.


Juncus stygius Linnaeus var. americanus Buchenau - . 2n = ?.


Bogs, bog pools.


Juncus subcaudatus (Engelmann) Coville & S. F. Blake - . 2n = ?.


Swamps, bogs, shaded spring-heads, mossy woods.


Juncus subtilis E. Meyer - Creeping Rush. 2n = 40.


Muddy shores.


Juncus tenuis Willdenow - Path Rush. 2n = (40), (80), 84.


Roadsides, paths. [J. tenuis var. williamsii Fernald]


JUNCUS TORREYI Coville - . 2n = 40.


Shores, ditches, roadsides. From farther west and south.


Juncus trifidus Linnaeus - Highland Rush. 2n = 30, (40).


Exposed, rocky or sterile summits. [J. trifidus var. monanthos misapplied]


Juncus tweedyi Rydberg - . 2n = 80.


Shores, bogs, marshes. [J. brevicaudatus (Engelmann) Fernald -- invalid name]


Juncus vaseyi Engelmann - . 2n = 42, ca. 80.


Swamps, shores, thickets.


JUNCUS hybrids


Juncus articulatus Linnaeus X J. tweedyi Rydberg - .



Juncus nodosus Linnaeus X J. tweedyi Rydberg - .



Juncus x oronensis Fernald (pro species) - .


Alder swamps, thickets. [J. tenuis Willdenow X J. vaseyi Engelmann ?]


Juncus secundus P. Beauvois ex Poiret X J. tenuis Willdenow - .



Juncus tenuis Willdenow X J. vaseyi Engelmann - .




JUNIPERUS (Family: Cupressaceae)


JUNIPERUS COMMUNIS Linnaeus var. COMMUNIS Pursh - Common Juniper. 2n = 22.


Woodland clearings, cemeteries. From Eurasia.


Juniperus communis Linnaeus var. depressa Pursh - Ground Juniper. 2n = 22.


Poor soils in open areas, especially old pastures and ledges, persisting in recent woodlands. [Larger individuals have been misidentified as var. COMMUNIS.]    CONN herbarium image


Juniperus horizontalis Moench - Creeping Juniper. 2n = 22.


Ledges, sandy or rocky banks.    CONN herbarium image


Juniperus virginiana Linnaeus var. virginiana - Eastern Red Cedar. 2n = 22.


Mostly dry, open sites (typically old fields), rocky slopes, borders of salt marshes, persisting in recent woodlands. [J. virginiana var. crebra Fernald & Griscom]    CONN herbarium image

Juniperus hybrids

Juniperus communis Linnaeus var. depressa Pursh X J. virginiana Linnaeus var. virginiana.



Juniperus horizontalisMoench X J. virginiana Linnaeus var. virginiana.




JUSTICIA (Family: Acanthaceae)


Justicia americana (Linnaeus) Vahl - . 2n = 26.


Margins or shallow beds of streams.





Designed by Ray Angelo. Revised June 13, 2022