over and desiccate a water area, especially if the area is small and shallow. It 

 has been found that mowing cat-tails after their heads are formed but still im- 

 mature, followed by a second mowing a few weeks later, will control these plants 

 to a considerable degree. 



1. Staminate and pistillate portions of spike usually contiguous; stigmas ligulate 

 to lanceolate; sterile ovary ellipsoid, tipped at the rounded apex by 

 a rudimentary style; leaves flat on back 1. T. latifolia. 



1. Staminate and pistillate portions of spike usually separated by an interval; 



stigmas linear to filiform; sterile ovary not ellipsoid; leaves com- 

 monly convex on back (2) 



2(1). Leaves 5-8 mm. wide, dark-green; sterile ovary cuneate, with a rudimen- 

 tary style on the truncate-flattened apex 2. T. angustifolia. 



2. Leaves 7-15 mm. wide, light-yellowish-green; sterile ovary obovoid, the 



rounded apex tipped by a short rudimentary style 



3. T. domingensis. 



1. Typha latifolia L. Common cat-tail, tule espadilla. Fig. 24. 



Plant coarse and stout, to about 3 m. tall; pith of the stem base white; leaves 

 essentially flat, sheathing, pale- or grayish-green, 6-23 mm. wide, often exceeding 

 the stem; sheaths cylindrical but open to base, the scarious upper margin tapering 

 to blade, rarely truncate or slightly auricled; the staminate and dark-brown pistil- 

 late parts of the spike usually contiguous, the staminate portion to 12 cm. long, 

 the pistillate portion to 2 dm. long, when in fruit 15-35 mm. thick, its surface 

 (when magnified) appearing minutely pebbled with crowded persistent stigmas 

 and scarcely bristly; pistillate flowers without bractlets among the bristles; stigma 

 ovate-lanceolate, fleshy, persistent; pollen grains in fours; denuded axis of old 

 spike retaining slender pedicels that are 1-2 mm. long. 



In marshes or shallow water and along streams throughout most of our area, 

 Mar.-May; from Nfld. to Alas., through most of the U. S. into Mex. 



2. Typha angustifolia L. Narrow-leaved cat-tail. Fig. 25. 



Plant slender, to about 15 dm. tall, the stem pith white; leaves mostly less 

 than 10, somewhat convex on back, dark-green, 3-7 mm. wide; sheaths appearing 

 cylindrical below but actually open to base, usually conspicuously auriculate 

 above, rarely with some sheaths tapering to the blade, the auricles scarious- 

 margined; pistillate and staminate parts of spike usually separated by a short 

 interval; pistillate portion of spike reddish-brown, in fruit to 15 cm. long and 

 15 mm. thick, its surface minutely bristly with persistent linear stigmas; staminate 

 portion of spike to 2 dm. long; pollen grains simple; pistillate flowers with a 

 linear fleshy stigma and usually with a hairlike bractlet with dilated blunt tips 

 among the bristles; the denuded old axis covered with stout blunt compound 

 papiHate pedicels that are 0.5-0.7 mm. long. 



In coastal and inland marshes in Okla. and mainly in s. Tex.; from N.S. and 

 s. Me. to s. Que. and Ont., s. to S. C, W. Va., Ky., Mo., Neb. and Tex.; also 

 Calif, and Euras. 



Fig. 26: Typha domingensis: a, fertile pistillate flower, showing mature ovary and 

 the surrounding hairs originating at base of stipe, bract attached, X 8; b, sterile pis- 

 tillate flower terminating in a swollen aborted ovary, hairs surrounding stipe in whorls, 

 X 8; c, aborted obovoid ovary tipped by rudimentary style, x 20; d-f, typical bracts, 

 showing variations in the swollen tips, X 12; g and h, bracts of staminate flowers, 

 slender, simple or laciniate, with dark-brown shiny tips, X 12; i, 1 -celled pollen grains, 

 grains occasionally in pairs; j and k, compound pedicels of pistillate spike, j, X 9, 

 k, X 40; 1 and m, spike, showing area of separation between the staminate part 

 (above) and the pistillate part (below), X %; n, pistillate spike, X %. (From Mason, 

 Fig. 7). 



87 



