Agriculture Reference
In-Depth Information
Artichoke and relatives
ASTERACEAE
Asteraceae is the largest and most diverse family, with members found all over the world. Its
ranks of ornamentals alone are legion—everything from A for aster to Z for zinnia; the gen-
era to which our crop plants belong are few in comparison. Still, it's hard to imagine a veget-
able garden without lettuce, while others in the family, like burdock, are hardly thought of as
crops at all. Most aster family plants have an aromatic scent and tangy flavor. Many store in-
ulin (not to be confused with insulin) in their roots instead of starch; inulin is a sugar that
diabetics can consume. An occasional family characteristic is production of a milky white or
cream-colored fluid.
BOTANICAL CHARACTERISTICS
Individual flowers stand upon spherical or hemispherical, recessed
“baskets.” The previous name of the family, Compositae, and the derived common name “composite”
(which is still used colloquially) refer to this floral arrangement. What we call the flower is, botanically
speaking, a basket-shaped flowering head composed of numerous individual sessile flowers, each of
which produces one seed when fertilized. Another common characteristic is the pappus, the feathery
bristles that help the seeds be carried by the wind.
GENERAL PROPAGATION CHARACTERISTICS
Aster family plants have perfect flowers. Most mem-
bers are self-fertile outcrossers, running the gamut from strict self-pollination to principally cross-pol-
lination; lettuce is a typical selfer that rarely cross-pollinates. The individual flowers of a flower head
can sometimes pollinate each other. For sunflower, salsify, or scorzonera, out-crossing is the rule, but
self-pollination can occur. Artichoke, cardoon, and others pollinate only through insects.
The individual flowers of aster family plants occur in a basket-shaped flowering head.
Overview of the aster family
COMMON NAME
GENUS
SPECIES
lettuce
Lactuca
sativa
endive
Cichorium
endivia
