ï~~ 166 THE MICHIGAN BOTANIST Vol. 50 NOTEWORTHY COLLECTIONS MICHIGAN Ilex opaca: Aquifoliaceae (American Holly) Previous knowledge. American holly (Ilex opaca Aiton) is a perennial, evergreen, dioecious shrub or tree in the Aquifoliaceae. It is native to the east coast from Massachusetts to Delaware and then inland in coastal states south to the middle of Florida and west to Texas and southeastern Oklahoma, reaching inland as far north as West Virginia, Kentucky and Missouri (Grelen 1990). In addition, the USDA Plant Database (USDA, NRCS 2002) has it in Maine, extreme southern Illinois and central and southern Ohio. Overlease and Overlease (2007) list it from the southern third of Indiana, reproducing from introduced ornamental plantings. In La Porte County, they recorded several mature trees, but no seedlings or saplings (Overlease and Overlease 2007). Neither Voss (1985) nor Swink and Wilhelm (1994) lists American holly from Michigan. In Pennsylvania, American holly is listed as a threatened species and in New York as "exploitably vulnerable" (USDA, NRCS 2002). Significance of the report. We report the first occurrence of American holly in Michigan, specifically in Allegan and Berrien counties. I. opaca (Figure 1) was first found in 2002 at two sites on old beach sands from post-glacial lake beds near Saugatuck. At these locations, which are about 3 km apart, numerous small, vegetative trees were growing in shaded, sandy soil in a southern mesic forest and an overgrown mixed pine plantation. In 2009, at the Berrien County locale, which is about 100 km south of the Allegan County sites, we found three small, vegetative individuals growing about 30 meters apart in a sandy, second growth, southern mesic forest at Tower Hill Retreat and Camp north of Sawyer. The Berrien County site is about 30-50 km north of the La Porte County site reported by Overlease and Overlease (2007). In 2010, three more small American holly plants were found in an old white pine plantation in St. Joseph. This site is about 20 km NNE of the 2009 Berrien County site. At all of the locales described herein, the American holly plants are probably escapes from cultivation. Our locales are about 400 km from the nearest naturally occurring populations, a distance that seems too great for non-human seed transport. Because birds and/or mammals are known to disseminate the seeds of American holly (Daubenmire 1990; Engstrom et al. 1984), some of these animals may have transported fruits and/or seeds to the woods nearby from some cultivated parents. In Allegan County, one of us (W.M.) found two mature trees across the road from one collection site and about 3 km from the other (Figure 2). The trees, a male and a female, had been planted adjacent to a home. We hypothesize that birds consumed the fruits from the female tree and then defecated the seeds at the collection sites. We also suspect that in Berrien County mature trees (both male and female and growing in close proximity to each other) also
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