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... One of the first flowers of spring on upland prairies and dry hillsides,
spiny phlox usually occurs concurrently with pasque flowers.This compact,
mat-forming perennial is only a few inches tall. Leaves are opposite,
linear, up to about \textfrac1/3 inch long and \TextFrac{1}{16th} inch
wide. Flowers are solitary and terminal. The petals are white, forming a
short tube with 5 lobes at right angles to the tube, and with a yellow
throat; the lobes are up to \TextFrac{1}{3} inch long and \textfrac1/6th
inch wide. The fruit is a small oval capsule ...

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