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INSECT PESTS:

IPM/A -20~

2. In spring, spot treat perennial weeds such as Canada
thistle with weed oi] or ammonium sulfamate {the two

Jeast-toxic herbicides known to be effective on

TomeemetemeMh em SAS HSN NR in WANNA HLUHE Eo e8Utant ae Sane doar

thistles). Once the weeds are dead, disk the weeds to

create a seed bed, apply fertilizer and sow a mix of
annual and perennial rye grasses. These grasses release
toxins in the soil which will tend to inhibit ger-
mination of jthistle seeds. NOTE: If herbicide treat-
ments are not quickly followed by seeding of desired
grasses, the most probable result will be the regenera-
tion of young thistles to take the place of the ones
killed by the herbicides...

3. Monitor the areas where thistles have heen treated
to insure that grasses are becoming established. Apply
additional grass seed or fertilizer if necessary. One or
two mowings might speed up grass establishment. lf this
is done, leave clippings on the ground. This increases
shading at the soil level and discourages the ger-
mination of. many broadleaf weed seeds including thistles.

4. To the degree feasible, restrict activities which
disturbs soil on the slopes of the dykes. Broadleaved
weeds such as thistles have a difficult time becoming

established in undisturbed soils.

A number of insect pests are of concern to city staff.
Recommendations for an IPM approach to managing these
pests are too complex to be handled in one consulting