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| Diagnostic Characteristics | Lilaeopsis schaffneriana var. recurva grows in perennial, shallow and slow-moving water. Such sites are rare in southeastern Arizona and northern Sonora, Mexico. Lilaeopsis is difficult to locate in the field, in part because it usually occurs with and resembles another small wetland species, Eleocharis charibea. Lilaeopsis has semisucculent leaves that are somewhat flexuous, whereas Eleocharis leaves are pithy, strictly straight and not at all succulent. The leaves of Lilaeopsis also appear to be a pale yellow-green compared to the darker green of most co-occurring herbaceous species.
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| Ecology | Affolter (1985) observed flowering specimens from collections made in June and August and fruiting specimens from May and July through early September. Nature Conservancy botanists have observed Lilaeopsis flowering abundantly only once (April 1988), as the local conditions were drying out at Cottonwood Spring along Sonoita Creek. Flowering at low frequency has also been observed from March through October. <br><br>Affolter (1985) suspects that other members of the genus Lilaeopsis self-pollinate. Seed germination from plants grown in an aquarium has been observed. The seeds stuck to the aquarium sides after falling from the parent plants and germinated within 1-2 weeks after ripening (Warren, pers. comm.). Although seeds from Lilaeopsis schaffneriana var. recurva appear to germinate easily, vegetative reproduction via rhizomatous spreading and dispersal of dislodged clumps is clearly important. Liz Ecker, curator of the Living Collection at the Desert Botanical Garden, has a living specimen which has flowered and born fruit, but she has done no germination studies with the taxon to date (L. Ecker, pers. comm.). <br><br>An experimental transplant program for Lilaeopsis was conducted at the San Bernadino National Wildlife Refuge in 1991 in order to establish a second secure population on the refuge that would be less vulnerable to destructive flooding than the existing population on Black Draw. Aside from securing a population, the project allows us to learn more about the ecology and habitat of the species for future management (Warren 1991). <br><br>Three transplant sites were chosen at perennial ponds. The first transplant took place August 26, 1990; the two subsequent transplants were made on March 2, 1991, with follow-up monitoring of the transplants done on April 26, 1991. The three transplant sites yielded different results. Lilaeopsis could not be relocated at the first transplant site. Competition with other herbaceous plants appeared to have wiped out the transplanted colony. At the second site the Lilaeopsis transplant persisted, but due to a moderate amount of surrounding competitive vegetation, the patch did not grow beyond its original 5-inch diameter. However, the third site which was relatively free of competing vegetation, showed tremendous growth and vigor - increasing from 5 inches to approximately 2 feet in diameter over the 1.5-month period. <br><br>The major conclusion is that Lilaeopsis can not survive where there is heavy competition from other herbaceous aquatic plants. Shallow standing water, in contrast to flowing streams, is grown in quickly with aquatic vegetation. Therefore Lilaeopsis grown at ponds may need special management to reduce density and accumulated litter from competing vegetation. Lilaeopsis is a vulnerable taxon which is easily destroyed by heavy flooding and scouring of habitat, although it also appears to need some amount of disturbance to the habitat in order to decrease surrounding competitive vegetation. Lilaeopsis appears to grow year round in the absence of killing frost whereas other aquatic plants tend to die off during the winter, allowing Lilaeopsis to more effectively colonize open space following low-level disturbance. <br><br>Census data: <br><br>The Nature Conservancy established and monitored transects at three Lilaeopsis locations in 1989. Transects were established at Scotia Creek and Bear Creek in the Huachuca Mountains and another at Cottonwood Spring along Sonoita Creek near Patagonia. The location (distance along the transect), length, and width of every Lilaeopsis patch along permanent transects was recorded. The density of leaves in each patch was also estimated using a rank scale. Lowest density patches received a 0.5 ranking, and highest density patches ranked 3.0. The rank-density value for a sample of patches was correlated with actual stem counts in 12cm x 12cm quadrants to calibrate the scale. Using these counts, a mean density (number of stems per 0.01 square meters) was calculated for each density rank (Gori et al. 1990). <br><br>Density and coverage of Lilaeopsis varies greatly from site to site. Percent coverage of Lilaeopsis varied among the sites from 11.5% to 58.3%; of the total area occupied by Lilaeopsis, 10.4% to 75.3% had a density value of 2.0 or greater. For specific data see Gori et al. (1990). Together these data provide a profile of the distribution and density of Lilaeopsis schaffneriana var. recurva along transects in 1989. Similar measurements in subsequent years will indicate what changes have occurred in these streams. The fate of individual patches can also be tracked since the position, length, width and estimated leaf density of every patch is mapped along each transect. <br><br>Related species: <br><br>The genus Lilaeopsis contains 13 species of perennial, rhizomatous herbs which live in temperate and alpine regions of North and South America and Australasia. These plants grow in damp, marshy and aquatic habits, often in brackish water. Lilaeopsis schaffneriana is one of 4 strictly freshwater species in the genus. It occurs in southeastern Arizona, central and northern Mexico and northwestern South America (Affolter 1985). <br><br>There is a great deal of morphological variation within Lilaeopsis schaffneriana. Some is due to local environmental conditions, as Affolter (1985) showed when he reared plants from the same stock in different depths of water and got great differences in leaf length. Genetic differences, on the other hand, could easily arise among small populations which grow primarily by rhizomatous spreading. Affolter (1985) recognized the Arizona populations as a distinct subspecies based on differences in fruit shape as well as the major geographical gap across the continental divide between the ranges of the Arizonan and Mexican groups. <br><br>Lilaeopsis schaffneriana var. recurva inhabits disjunct locations in southeastern Arizona and northern Sonora. Known locations for Lilaeopsis schaffneriana var. schaffneriana are similarly separated on the central plateau of central and southern Mexico. This kind of distribution is expected for an aquatic species surrounded by arid lands. <br><br>Affolter expressed suspicion that the discontinuity between the subspecific ranges might reflect a lack of exploration for the plant. However, it is significant that the two subspecies of Lilaeopsis are found on opposite sides of the continental divide. So the predominant dispersal mechanism for the species, water, could not serve to mix populations (Warren 1991). <br><br>Lilaeopsis masonii is a candidate category 2 species of northern California. It grows along the margins of rivers, sloughs, and islands of the San Joaquin-Sacramento River delta (California Fish and Game 1988); there are approximately 30 known occurrences. Lilaeopsis masonii differs from L. schaffneriana var. recurva in that it is found in intertidal zones of brackish water marsh. It grows far enough inland so it does not grow directly in salt water as some species of Lilaeopsis, but the water is brackish and the plants do experience tidal fluctuation (R. Bittman, pers. comm.). <br><br>Lilaeopsis masonii grows in dense mats at water margins. Associated species are: marsh pennyworts (Hydrocotyle umbellata and H. verticillata), three-ribbed arrow grass (Triglochin striata), mudwort (Limosella subulata), tules (Scirpus spp.), rushes (Juncus spp.), and Suisun marsh aster (Aster chilensis var. lentus). <br><br>Lilaeopsis masonii grows from an elevation of sea level to 25 feet. It flowers from April to October. Little is known about the ecology/biology of this species (R. Bittman, pers. comm.). <br><br>The primary threats to Lilaeopsis masonii are proposed water projects which involve dredging, rip-rapping, levee construction, and other alterations to natural banks and river channels. Heavy cattle grazing also occurs at some of the sites. Petroleum processing plants exist in the area and the species is vulnerable to oil spills. One spill impacted two populations in 1988. The long-term effects of oil on the species is unknown (California Fish and Game 1988). <br><br>No recovery programs are currently necessary for Lilaeopsis masonii, but the species is of interest here because proposed management for the species includes an experimental transplant program. Rip-rap work has been proposed along Barker's Slough in Solano County. This could potentially destroy dense colonies of Lilaeopsis masonii. A project to transplant all Lilaeopsis masonii at the rip-rap sites to suitable habitat has been proposed. Information gained from California's transplant program may prove useful to our efforts at managing Lilaeopsis schaffneriana var. recurva.
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| Habitat | SUMMARY: Cienegas (mid-elevation wetland communities), riverine systems, and springs at about 1150-2130 m elevation. Usually in wet soils along the periphery of a channel, in backwaters, or in small openings in the understory near springs. Does not tolerate much competition with other species, but will quickly colonize open habitat created by scouring floods and persist there until interspecific plant competition becomes too great. In order for populations to expand, some plants must remain in areas that escape the effects of periodic scouring floods. END SUMMARY. Lilaeopsis schaffneriana var. recurva is restricted to cienega habitats, which are marshy or meadow-like wetlands surrounded by semiarid vegetation (Warren 1991).`Hendrickson and Minckley (1984) describe three different types of cienegas based on elevation: low, mid, and high elevation cienegas. Low elevation cienegas or subtropical marshes occur mostly along major perennial rivers below 3000 feet. The low elevation Lileaopsis sites have experienced the most disturbance, both human and natural. Low elevation cienega habitats were probably river backwaters and floodplain seeps. These locations are very unstable, experiencing cycles of flooding and drying due to varying climatic patterns. Human influence including groundwater pumping and diversion of water for irrigation have eliminated perennial flow in most southeastern Arizona rivers. Perennial flow is essential for wetland formation. This loss of habitat is evident in the disappearance of 4 historic locations of the taxon. Grazing has added to the problem by contributing to watershed deterioration, which exacerbates erosive flooding and further destabilizes cienega habitats. There are 2 known sites occurring at low elevation on the same stream; one is in the San Bernadino National Wildlife Refuge, in the U.S., and the other in Sonora, Mexico near the border along the Rio San Bernadino. <br><br>Mid-elevation cienegas occur between 3000-6000 feet. This elevation range fits Hendrickson and Minckley's (1984) definition of true cienega habitat. Permanent water is available and a unique wetland community has developed at these sites (Warren 1991). Flooding potential is lower at these cienega sites because they have smaller drainage areas. Also, the gradients are gentler at these mid-elevation sites as opposed to the higher elevation cienegas. There are 6 current U.S. locations for Lilaeopsis at mid-elevation sites, and 4 in Sonora; they are: Bear Canyon, Lone Mountain Canyon, Cottonwood Spring, San Rafael Valley (3 springs) and Turkey Creek in Arizona, and Ojo de Agua de Cananea, Rio San Rafael, Arroyo Los Fresnos and along the Rio Magdalena in Sonora. Flooding, however, is still a potential problem at this elevation range as demonstrated by the population at Cottonwood Spring, which was seriously reduced by flooding from Hog Canyon in 1988. Grazing also has a negative impact on this watershed. <br><br>High elevation cienegas occur at elevations over 6000 feet. They are described by Hendrickson and Minckley (1984) as "marshy to bog-like alpine and cold temperate meadowland." They may form in surface depressions that fill with water or at stream headwaters. There are few potential sites for Lilaeopsis at these elevations because usually these higher sites are in canyons with stream gradients too steep to support cienega wetlands. Three high elevation sites of Lilaeopsis are known in the Huachuca Mountains. One is in upper Scotia Canyon and another in upper Garden Canyon. An additional Lilaeopsis population is reported in Sunnyside Canyon from 6050-6200 feet (S. McLaughlin, pers. comm.). <br><br>The surrounding vegetation of the cienega communities varies with elevation. Willow (Salix spp.) and cottonwood (Populus spp.) trees, cattails (Tyogys sp.), large reeds, bulrush (Scirpus spp.), and halophytes in nearby saline areas are typical of desert-scrub communities of the low elevation cienega sites. Rushes, grasses, fewer cattails, semiaquatic sedges, watercress (Nasturtium officinale), water pennywort (Hydrocoytle americana), halophytes in adjacent saline areas, and trees (not as common with willows being the most common) are the dominant species of the grassland/oak woodland habitat of mid-elevation cienegas. Finally, the high elevation community is conifer forest including cold-resistant sedges and rushes, semiaquatic and terrestrial grasses, and low, woody alder (Alnus spp.) and willow (Salix spp.) shrubs. <br><br>Physical factors, particularly hydrological conditions such as watershed area and stream gradient, appear to limit the distribution of Lilaeopsis schaffneriana var. recurva. The taxon appears to have specific requirements which limit its distribution to perennial water, gentle stream gradients, small- to medium-sized drainage areas and mild winters. <br><br>Weather and precipitation data (NOAA 1986) from stations within the range of Lilaeopsis: <br><br>At Canelo 1 NW station in Santa Cruz county, the data are summarized as follows: elevation 5010'; N latitude 31 33'; W longitude 110 32'; mean annual precipitation 17.06"; January mean temperature (F) 42.2; July mean temperature (F) 74.2; and annual mean temperature (F) 57.2. <br><br>At Douglas FAA station in Cochise County, the data are summarized as follows: elevation 4098'; N latitude 31 28"; W longitude 109 36'; mean annual precipitation 12.16"; January mean temperature (F) 44.9; July mean temperature (F) 79.1; and annual mean temperature (F) 61.6. <br><br>Because the Lilaeopsis sites are so dispersed, climatic data provided here are relatively non-specific. Populations inhabit the physiographic province known as the Sonoran Desert Section of Basin and Range. <br><br>The hydrologic regime appears to be a critical aspect of Lilaeopsis habitat. In an effort to characterize hydrologic conditions at each site, we estimated site substrate stability and watershed gradient above the site based on visual observations of the sites. We have made a somewhat arbitrary classification of stream channel conditions at each site as "stable" or "unstable" based on the condition of herbaceous vegetation along the stream bank and channel: stable sites are those where the stream banks, and part or all of the channel, are well stabilized by herbaceous vegetation; unstable sites are those where the channel and much of the banks are unconsolidated, shifting alluvium. Under present watershed conditions, 10 square miles appears to be a watershed size threshold above which flooding is too severe for Lilaeopsis to persist, although larger watershed area may be mitigated by low gradient, as at San Bernadino. <br><br>This taxon does not tolerate much competition with other species, but will quickly colonize habitat disturbed by scouring floods and persist there until interspecific plant competition becomes too great. In order for populations to expand, some plants must remain in areas that escape the effects of periodic floods (Rutman and Rorabaugh 1995).
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