Biodiversity is affected through a variety of means. Landscaping with non-native plants that adapt well to a new climate, for example, can allow the non-native plant to spread at the expense of native plants. Ranching has led to problems in places such as Death Valley, a fragile ecosystem where hardy grasses that were originally introduced into neighboring ranges for sheep ranchers, have invaded and outcompeted indigenous and rare species within Death Valley itself. Climate change may also be facilitating the loss of biodiversity. In other words, warmer springs not only lengthens the growing season for farmers, but also allows some non-indigenous species (sea squirts, in this instance) to outcompete native species. The mean temperature throughout the year is of less importance than whether temperature is warmer, in the winters.