the extremes, I'based on fruit-characteristics, as C. (jlahra and C. in'olis. It should 

 be pointed out that Manning, Rhodora 52:191, 1950, stated that he was unable 

 to separate these s-pecies except with completely mature fruit : because of the excessive 

 variability of C. n-c'dlis we consider it inadvisable to recognize any of its so-called 

 varieties in New Hampshire. 



C. glabra (Mill.) Sweet Pignut. 



Warm, dry and often rocky slopes, Durham, .StratTord County, and Newmarket. 

 Rockingham County, and probably elsewhere in southern New Hampshire ; local and 

 mucli less common than the next. 



C. ovalis (Wang.) Sarg. Sweet Pignut. 



Southern Strafford and central and southern Rockingham counties ; warm, dry 

 and often rocky slopes; also in some profusion in southeastern Hillsboro and soutli- 

 western Cheshire counties. 



Corylus americana AX'atts. American Hazelnut. 



At low elevations in central and southern New Hampshire reaching north to 

 Haverhill and Ossipee ; of somewhat scattered distribution, common southward ; 

 thickets in both dry and moist situtations : forma iiiissDuriciisis {A. D. C.) Fern., 

 with glandless twigs, petioles, and involucres is less common hut occasional. 



C. cornuta Marsh. Beaked Hazelnut. 



Widely distributed and common throughout in well drained sites ; thickets, road- 

 sides and OTen woods at low elevations occasionally ascending to .1,000 feet; specimen 

 from Keene with few bristles approaches forma iucnnis Fernald. 



Ostrya virginiana (Mill.) Koch. Hop-Hornbeam, Ironwood. 



Frequent and widely distributed at low elevations throughout ; rich, often rocky, 

 v/arm slopes: forma glaiidiilnsa (Spach.) Macbr., with branchlets bearing glands, 

 occurs throughout our range. 



Carpinus caroliniana Walt. var. virginiana (Marsh.) Fern. .American Hornheam, 

 Blue Beech, Ironwood. 



Locally common in swamos and low, rich woods in southern New Hampshire ; in- 

 frequent in central New Hampshire : north to Bath in Connecticut Valley, Canter- 

 bury in Merrimack \'alley and Wolfeboro in eastern New Hampshire. 



Betula lenta L. Black, Cherry-or Sweet Birch. 



Conunon forest tree of good soils at low elevations in southern and south central 

 New Hampshire, north to Hanover in Connecticut ^"alley and to Tamworth in 

 eastern New Hampshire: Rhodora 13:206-207. 1911: forma laciuiata Rehder with 

 deeplv cut leaves was described from a specimen collected in New Boston : Rhodora 

 4:83-84, 1902, and 9:111, 1907. 



B. lutea Michx f. var. lutea. Yellow Birch. 



Common and of wide distribution ; climax-species of moist, cool forest up to 2,000- 

 feet elevation ; occasionally occurring to 3,000 feet : forma falla.v Fassett, having close 

 bark, has been collected in Albany. 



Var. macrolepis Fern. 



Of scattered distribution in northern and central parts of the state ; outlying 

 station in Manchester; less common than the typical, but associated with it and 

 freely intergrading. 



B. nigra L. River-or Red Birch. 



Southern species locally abundant in Merrimack Valley, extending north to Beaver 

 Brook in Pelham ; limited colony also on southeastern shore of Mendum's Pond, 

 Barrington, at northeastern known limit of ranse : said also to be found on an island 

 in Pawtuckawav Lake ; Barrington colonv much expanded in recent vcars : Rhodora 

 37:414, 1935. 



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