Illustration of a perennial plant growing over two years, with bee nests inside old stems in the second year. Insets show nest interiors, one with larvae and one with adult bees.

Figure 2. Seasonal cycle of stem growth in a perennial plant. In year one, flowering stems grow and die. If they are trimmed in their first winter, they are available as nesting and overwintering habitat throughout the following year—shown here with small carpenter bees in the genus Ceratina.

Illustration of a perennial plant growing over two years, with bee nests inside old stems in the second year. Insets show nest interiors, one with larvae and one with adult bees.

Illustration by Christina Spence Morgan CC BY-NC-ND 4.0