The Dandelion in Colorado 
33 
appear in considerable numbers, it indicates that the conditions 
are in some way unfavorable. The appearance of numerous weeds 
in the alfalfa, which seem to be crowding it out, calls for a careful 
study of the soil and moisture conditions, and the presence of dis¬ 
eases and injurious insects and animals and the system of manage¬ 
ment, to determine what corrective measures, if any, can em¬ 
ployed. 
SUMMARY 
1. The common dandelion is our most noticeable and persist¬ 
ent weed in lawns in Colorado. It sometimes becomes a bad weed 
in meadows, pastures and in alfalfa fields where the stand is be¬ 
coming thin. 
2. The plant gains entrance and spreads by means of its wind- 
wafted seed-like fruits. Irrigation water taken from ditches along 
which the weed grows plentifully may also carry the ‘‘seeds” onto 
the land. As the plant gets older, the tap root may split up into 
several strands by a natural process of division and thus produce 
large clumps. Any part of the root, when cut off and left in the 
soil, may sprout and produce a new plant by means of adventitious 
buds. 
3. The dandelion plant does not produce blossoms and fruit 
during the first year from seed. Its most profuse period of bloom 
and seed is during May and June. About nine days elapse between 
the first opening of the flower heads and full maturity of the seeds. 
Only a very small percentage of the seeds are mature enough to 
germinate by the seventh day following first blooming* of the 
flower head. Flower heads picked or cut off when in bloom and 
left to lie on the lawn will not produce mature seed, capable of 
germination. 
4. The dandelion has no serious natural enemies capable of 
keeping it under control. Certain seed-eating birds consume large 
numbers of the ripening seeds and thereby reduce the number 
scattered. 
5. The dandelion can be controlled in lawns by persistently 
employing one or a combination of the following methods: 
(a) By establishing the lawn on a carefully prepared seed 
bed with the best grade of lawn grass seed obtainable. A mixture 
containing 10 per cent of white clover seed is desirable when 
quicker results are wanted in securing a soil cover. Dead spots 
and thin places in the sod of old lawns should be re-seeded each 
year to maintain as dense a growth as possible and thereby dis¬ 
courage the entrance and growth of weeds. Early spring is the 
best time for this renewal seeding*. 
