The Manual of Vascular Plants of Butte County reports that Calabazilla is occasional in fields, along roads and in disturbed habitats on the Valley Floor. Humans have been implicated in the spread of this species throughout its present range. One investigator even suggests that the spread of Calabazilla north of the Colorado River into California is likely the result of Native American trade and travel. Wherever the plant gets, it is likely to stay for a while. I am aware of one fellow Chico botanist who planted a seed next to his driveway years ago, and who, to this day offers a reward for its permanent removal.
Calabazilla is a very vigorous botanical specimen, to say the least.
This root system gathers and hoards infrequent rainfall and allows the phenomenal seasonal production of foliage. Calculations estimated that 15,720 leaves were produced by these annual stems in just one season. Although plants can produce more than 200 fruit with 200-300 seeds per fruit, most reproduction in a population seems to arise from rooting of the long vines. During your travels around California's Central Valley and beyond, keep a lookout for this somewhat peculiar ambassadore from the vegetable kingdom. It is usually visible on the roadsides even when viewed from a passing car window.