Table Of Content

American Fern Journal 85(3):95-97 (1995) Shorter Notes — nudum New The Psilotum Arkansas. pantropical pteridophyte Psilotum to nudum Beauv. distributed in the United States across the Atlantic (L.) P. is Coastal Plain from Florida to North Carolina (Perry and Musselman, Amer. Fern 84:102-104, 1994), across the Gulf Coastal Plain from Florida to Texas J. (Lodwick, Amer. Fern and Arizona Flora 65:62, 1975), disjunctly in [Thieret, J, of North America 2:16-17, Three populations, one natural and two ad- 1993). were ventive, discovered recently in Arkansas. In the U.S., these populations are most distant from oceanic moderation and most exposed to interior con- km They northward 200 from tinental climate. extend the species' range re- The ported populations in Texas and Louisiana (Rhodes, Sida 3:525, 1970). populations are suggestive that other populations might be located in the southern half of Arkansas, and perhaps in other northerly locations in the Southeastern United States. In autumn of 1992, the Arkansas population was noticed while doing first yardwork. The population was located within Arkadelphia, Clark County, by Dennis McMasters. While raking, he located a single stem that was sheltered was by a rock retaining wall and by a thick covering of English ivy. protected It on sides from direct sunlight, and was observed for three years before a all were voucher was removed [McMasters 95001, HSU). Preliminary observations autumn reported (Bray Proc. Arkansas Acad. 48:239-241, 1994). In et Sci., al., of 1993, two stems were observed; in autumn of 1994, three stems were ob- cm The by and served, each 10 thrice branched, etiolated shade, sterile. tall, mulch from im- population ^most probably originated horticultural soil or to prove landscaping. The McMasters family was involved in the greenhouse The Henderson Uni- business Arkadelphia, but did not Psilotum. State in sell km (HSU) campus, away, has greenhouse with Psilotum. Thus, versity 1.5 a may the population probably adventive and have arisen as a waif or escape is from might have been introduced with land- a local source; alternatively, it scaping materials trucked northward to Arkadelphia from nurseries to the km south. This population 200 north of the nearest population in Texas or is now growing suggesting Louisiana; has been observed in four seasons, it is it and become whether can reproduce well remains be seen established. to It it naturalized. On February 1994, a natural population was discovered by the senior 12, swamp author the edge of a Nyssa aquatica/Taxodium distichum adjacent at an impoundment extreme southern a gravel timber access road bordering in to R24W Management Area Lake Arkansas (T19S Lafayette Wildlife at Erling, S2, Lafayette County, Peck 94003, LRU). The population was discovered by ser- cm by and The above-ground stems were 10 etiolated shade, endipity. six tall, was browsed by Only one stem observed two stems were stunted, deer. sterile; probably in March 1995. The population appears to be naturally occurring, may be but not self-replicating. the result of a long-distance colonization event, — MERICAN FERN VOLUME 96 JOURNAL: was Amason discovered by on Carl January While growing two plants in partially-shaded sidewalk m supported that 2.5 ^ _.._^. ^ ^ , ings were established in 1984. The source greenhouse has never carried Psi- um. most Therefore, it is likely that the plants originated from mulch trucked northward cm filler to El Dorado. These plants are than being etiolated, these plants have the stem grow wa ;e material; thev in a narrow but sunnv The that slopes southward. plants occur on the run-off water. After being informed im of the growing bank in their landscaping, the officers uniformed guards showing delight in off the plants to botani; plants from customers. H. Peck, Department ^James Bray James R. Marsh, and Dennis W. McMasters, Department AR AR Arkadelphia, Carl Amason, 71999; and Calion, 71724, Winfred Crank D. Growth Estimated revious paper Amer. Fern (Seller, 71:75-81, 1981), investigated the I J. demography and growth of Alsophila Hook, Bosaue Monte- salvinii in estimated the July Montecristo and measured some srowth the actual of the trees used in the 1978-80 study. The actual growth i% of the original estimated rate. In June 1978, I tied flagging tape to the bases of stipes July the original 28 trees from the remnants of the flagging tape on them. Seventeen of the 18 were trees determined growth between still alive. the of the I trees and June 1978 July 1991 by measuring between the distance the flagging tape and crown the The mean of the plant. growth of the during 1 7 living trees that was 95% period cm; 66.1 the confidence growth ±0.8 interval the for rate 5.1 is The cm/yr. range is 2.3 to 7.7 cm/yr. my arithmetic May rate is recalculated here. For the period from 1979 May 95% to 1980, the mean confidence limits for the frond production rate are 2.5 ±0.8 fronds/yr [n = In January 1979, counted cm 10). stipe bases in 50 sections of the apical I 95% part of the trunk on 10 mean confidence trees; limits for the are 18.1±1.1 cm. Thus, growth the rate calculated from 1978-80 is: