The Dandelion in Colorado 
33 
appear in considerable numbers, it indicates that the conditions 
are in some way unfavorable. The appearance of numerous weeds 
m 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 bp em¬ 
ployed. 
SUMMARY 
I 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. 
i 3. The dandelion plant does not produce blossoms and fruit 
f durin ff the first year from seed. Its most profuse period of bloom 
and seed is during May and June. About nine days elapse between 
i the first opening of the flower heads and full maturity of the seeds, 
j Only a very small percentage of the seeds are mature enough to 
germinate by the seventh day following first blooming of the 
| dower 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. 
« 
j' 4. The dandelion has no serious natural enemies capable of 
keeping it under control. Certain seed-eating birds consume large 
J numbers of the ripening seeds and thereby reduce the number 
1 scattered. 
5. The dandelion can be controlled in lawns by persistently 
j 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. 
