Prenanthes altissima (Nabalus altissimus) tall white lettuce Asteraceae PRAL; Q, cu; R;

Prenanthes altissima.Robbin

Prenanthes altissima.Robbin Moran.NY Bot. (Accessed 4/2014).

Prenanthes altissima is a perennial herb, 0.40 – 2 m tall, sap milky. 

Leaves alternate, lower leaves long-stalked, upper leaves reduced, short-stalked, blade 4-15 cm long, 2.5-16 cm wide, very variable, egg-shaped, heart-shaped, triangular, often 3-5 parted, lobed or toothed, usually hairy below on veins. 

Flowers greenish-white to yellowish, all rays, 5-6, in very slender heads with bracteate base 0.9-1.4 cm long, main bracts 5, dark-tipped, heads nodding, inflorescence branched, leafy; Aug.-Sept. (Hough 1983). 

Fruit dry, achenes with cream-white plume. 

Wetland status: FACU-. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: Moist woods.

Notes: Recent DNA studies have classified all our Prenanthes as belonging to the genus Nabalus (Shilling et al. 2015).