Last updated: May 21, 2024
Place
Signs of Life, Self-Guided Tour Stop 9
NPS
Quick Facts
Location:
32.25465961390893, -111.1973309080446
Significance:
Tour stop
Designation:
NPS
Stop 9: Desert Mistletoe
This palo verde tree is heavily infested with desert mistletoe, a semi-parasitic plant. As you can see, the mistletoe is green, which means that it has chlorophyll and can produce its own food by the process of photosynthesis.
However, it gets its water and nutrients directly from the tree, rather than from roots in the ground. This does not normally kill the tree— there is no advantage for a parasite that cannot move to kill its host! The primary disperser of mistletoe is a bird called the Phainopepla. These members of the Silky Flycatcher Family (Ptilogonatidae), the only ones that come into the United States, migrate vertically: they winter in the desert and spend the warmer months in the mountains. During their time in the desert, a staple food item is mistletoe berries. The berries are digested, but the seeds pass through the birds’ digestive systems and are deposited with their sticky droppings on the branches of trees. The seeds grow into the wood of the tree to start a new mistletoe plant.
This palo verde tree is heavily infested with desert mistletoe, a semi-parasitic plant. As you can see, the mistletoe is green, which means that it has chlorophyll and can produce its own food by the process of photosynthesis.
However, it gets its water and nutrients directly from the tree, rather than from roots in the ground. This does not normally kill the tree— there is no advantage for a parasite that cannot move to kill its host! The primary disperser of mistletoe is a bird called the Phainopepla. These members of the Silky Flycatcher Family (Ptilogonatidae), the only ones that come into the United States, migrate vertically: they winter in the desert and spend the warmer months in the mountains. During their time in the desert, a staple food item is mistletoe berries. The berries are digested, but the seeds pass through the birds’ digestive systems and are deposited with their sticky droppings on the branches of trees. The seeds grow into the wood of the tree to start a new mistletoe plant.