The ecological niche of FLCP is centered in open, disturbed, fertile ground. It is an annual plant that becomes established each Spring as a seedling that germinates in loose soil at an open, sunny site. The seedling develops into a clambering vine that, through the use of tendrils, uses other plants as support to gain access to the sun. The size of the plant is limited by available nutrients and moisture. As elements of the native, riverine flora of North America, FLCP are adapted to climb tall trees of the native floodplain forests and gather light from the forest canopy. They are also able to form roots at each stem node (point of leaf attachment) if the node is in contact with moist soil. This allows horizontal converge of open areas (sandbars, river banks). Since new shoots can also be produced at each node, individual plants are able to access light through both ground and canopy cover. Thus, under favorable conditions, individual FLCP plants can be massive. Large, yellow, unisexual, bee-pollinated flowers, identical to those produced by domesticated squash (Fig. 4), are initially produced in late Spring. Flower production continues until the first frost. Large plants have the potential to produce 25-50 fruits, each containing 100-200 seeds. Seed dispersal is accomplished by the buoyant fruits which are typically deposited at the high water level during spring floods, often in fertile accumulations of 'drift' deposits along the river margin. Thus, FLCP is distributed along drainage systems and fertile floodplains within its range. As indicated above, these are also ecological centers of agricultural activity.

 The suite of structural and ecological factors expressed by FLCP are also manifested by other elements of the Cucurbitaceae that have been introduced into the North American flora and survive today as aggressive, economically important weeds. These include the 'Bur-Gherkin' (Cucumis anguria), the weed form of Muskmelon or 'Dudaim melon' (Cucumis melo var. dudaim), and the weed form of Watermelon or 'Citron' (Citrullus vulgaris var. citroides). While these plants rarely achieve 'top 10' ranking on State listings of noxious weeds, local infestations can represent a significant agricultural problem. This is also the case for FLCP.

 Population structure for FLCP in what appear to be 'native' areas within its range of distribution (Fig. 5 - 'B') is expressed by Correll and Johnston (1970) as "rare but abundant where found." High population densities within the native area could reflect annual situations where minimal Spring flooding has left fruits in place. However, this writer has observed a large, relatively permanent (10 years) population at Lake Sommerville, an impoundment of Yegua Creek in Burleson County, Texas. This population is apparently maintained and increased by water level fluctuations associated with the reservoir. These function to 'float' fruits into areas surrounding the impoundment, such as pastures and fields, that are not typical habitat. Subsequent colonization of these areas allows expansion of the population into areas where they could present a problem for the local human population, i.e., a transition to the 'weedy' condition as defined by the Weed Science Society of America. Thus, it would appear that the plant can take advantage of human-mediated habitat changes to 'invade' open ground beyond the drainage course, maximize population size, and thereby impact agricultural plant populations of the floodplain.

 This response does not appear to present a significant agricultural problem within the 'native' subareas (Fig. 5 - 'B') of FLCP distribution. It has, however, produced significant weed populations in Arkansas, Louisiana, Mississippi, Illinois, and Kentucky (Asch and Sidell, 1992). The plant is listed, as C. texana, as a weedy contributor to current crop losses in Arkansas (Bridges, 1992) and has been ranked among the top 10 weeds in that state for some time (McCormick, 1977). Large weed populations have been reported (Harrison et al., 1977;Oliver et al., 1983) from counties along the Arkansas and Red River drainages (Fig. 5 - 'C'). Ford Baldwin (pers. comm.) "knows of it along 100-km segment of Arkansas Valley, Clarksville to Conway, not south of Little Rock; and Red River, southwest Arkansas. Mostly occurs on very sandy, very well- drained overflow areas; very tenacious where established, but doesn't easily spread. A weed of soybean and rice" (Asch and Sidell, 1992). The plant is described as a "troublesome weed in field crops of the Arkansas and Red River bottomlands in Arkansas" with a "potential to spread to other areas within the Mississippi Delta" by Oliver et al., 1983). Reports from Mississippi and Louisiana suggest that this has occurred. Large, weedy populations of FLCP have been reported from soybean and cotton fields along the lower Yazoo drainage in Mississippi (D. Asch, C. Elmore, pers. com.;Asch and Sidell, 1992), and the Mississippi bottoms in northeastern Louisiana (D. Reynolds, pers. comm.;Smith, 1992). A small, local instance has been reported along the Red River floodplain just North of Shreveport in northwestern Louisiana (Smith, 1992). Asch and Sidell (1992) cite D. Sanders (pers. comm.); "A weed problem of cotton in north half of state; Red River and Mississippi River valleys. Not rare, but localized; an intense problem where it is established" and R. Rogers (pers. comm.) as indicating the FLCP is a weed problem "from 11 northeast parishes of Louisiana."

 While the weedy populations of Arkansas are evidently a perennial problem, reports from Mississippii and Louisiana are based on 'outbreaks' that are evidently linked to dispersal from sporadic flooding events and associated fruit dispersal into cultivated fields (C. Elmore, D. Reynolds, pers. comm.). Infested fields are "difficult to harvest and may have reduced yields" that result from "uncontrolled early-season or late-season gourds which entwine soybean plants and eventually cause soybean lodging" (Oliver et al., 1983). This also appears to be significant for FLCP populations in Illinois. Asch and Sidell (1992), citing communications with Kaskaskia Island (Randolph County) farmers R. Bartels and C. Jokerst, indicate, "Bartels recalls seeing plant on his farm as long ago as 1953 or 1954 when he was 12 or 13 years old. Plant became a serious field weed on island after it was widely dispersed by 1973 flood. Also spread by soybean combines. Bartels collected and destroyed 60,000 lbs. of gourds from a 140 acre field in 1987. Bartels has seen only round or pear forms; none long-necked or warty."

 Is FLCP difficult to control? How is it controlled?

 Asch and Sidell (1992), citing personal communication with G. Brown regarding FLCP as a weed in Kentucky, indicate that the plant is "prevalent in Union Co. (West Kentucky), but only in Ohio River Bottoms. A soybean-field weed, but also in corn if atrazine herbicide not used." G. Kapusta, also responding to questions from Asch and Sidell (1992) indicates that FLCP can be easily controlled by Atrazine in corn fields but, in Illinois, it is mostly a weed of soybeans due to wide rows and open habitat.

 Control of FLCP in soybean fields can be provided by preemergence application of metribuzin, metribuzin plus alachlor, and oxadiazon, although success depends of soil and climate conditions (Oliver et al., 1983). Adequate postemergence control can be obtained by treatments of acufluorfen, oxyfluorfen, and metribuzin plus 2,4-DB if applied at an early soybean growth stage and repeated (Oliver et al., 1983). However, effective chemical control in soybean fields has been complicated by the need for repeated applications due to "continual emergence of Texas Gourd under favorable conditions throughout the growing season" (Weideman and Templeton, 1988). Also, the mix of herbicide agents used for FLCP control in soybeans fields is not applicable for use in cotton fields (D. Sanders, pers. comm.). Tests by Oliver et al. (1983) indicate that "none of the herbicides evaluated provided a consistent level of Texas gourd control over all years and locations." Consistent control is difficult "since preemergence herbicides such as metribuzin are rainfall-dependent and postemergence herbicides must be applied by the V2 stage of soybean growth and repeated at the V4 stage or as needed." The literature provides no informatioin regarding mechanical control of FLCP weed populations. Continuous seed germination and a capability to root at the nodes probably minimize the efficacy of mechanical control. Thus, efforts are underway to perfect a biological control that targets FLCP specifically using 'mycoherbicides' (Yu and Templeton, 1983;Boyette et al., 1984;Yu et al., 1988). These efforts demonstrate that FLCP is a problem weed that can be difficult to control with traditional methods.

What is known about the viability, fertility, and ecological fitness of hybrids arising from crosses of FLCP and domesticated types of Cucurbita pepo?

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