CARYOPHYLLACEAE PINK FAMILY 
COMMON MOUSE-EAR CHICKWEED 
Cerastium vulgatum L. 
The Common Mouse-ear Chickweed is a native of Europe 
and northern Asia and is one of the many plants that have been 
accidentally introduced into this country from Europe. It is a 
perennial which has spread over 
nearly all of temperate North 
America, where it is found in fields, 
woods and dooryards, often be- 
coming a troublesome weed. 
The whole plant is covered with 
hairs and is usually somewhat clammy 
or sticky. The stems are 6-18 inches 
long and often repeatedly branched. 
They are sometimes erect but more 
often lean upon other plants or trail 
on the ground. 
Blooming occurs throughout the 
summer, from May to September, 
at first with the flowers clustered but 
as thestemsand flowerstalkslengthen, 
the inflorescence becomes 
very open. At length the 
pedicels are much longer 
than the calyx. The 
flower is composed of 5 
obtuse or acute green 
sepals, about equaling the 
5 white 2-lobed petals, 10 
stamens and I pistil with 5 
styles. The fruit is an 
elongated and somewhat 
curved, many-seeded cap- 
sule which opens by to teeth at the top. 
Since the plant blooms all summer and the fruits mature 
quickly, a very large number of seeds are produced each season. 
This ability to produce seed so abundantly is one reason why 
the Mouse-ear Chickweed has been able to spread extensively. 
