|
Volunteer, woody species should be controlled early in no-till systems.
Table 8. Weeds that may be found in no-till systems.
| Annuals (winter and summer) |
|---|
|
|---|
| annual smartweed | lambsquarter |
| black nightshade | marestail
/horseweed |
| common chickweed | pigweed |
| common ragweed | prickly lettuce |
| crabgrass | purple deadnettle |
| cutleaf evening-primrose | ragwort/groundsel |
| daisy fleabane | shepherd's-purse |
| downy brome | tansy mustard |
| fall panicum | Virginia pepperweed |
| foxtail | whiteheath aster |
| henbit | wild buckwheat |
| Japanese bromegrass | wild mustard |
| jointed goatgrass | wild oat |
| kochia | |
|
| Perennials and Biennials |
|---|
|
|---|
| bermudagrass | horsenettle |
| bigroot morning glory | Jerusalem artichoke |
| briars | johnsongrass |
| Canada thistle | poison hemlock |
| common burdock | quackgrass |
| common dandelion | redvine |
| common milkweed | Russian thistle |
| common mullein | smooth bromegrass |
| common pokeweed | swamp smartweed |
| curly dock | trumpet creeper |
| field bindweed | wild carrot |
| ground cherry | wild four o'clock |
| hemp dogbane | wirestem muhly |
| honeyvine milkweed | yellow nutsedge |
|
|
Many farmers, no matter the tillage system, have experienced weed
control failures. Unlike intensive tillage systems, conservation tillage doesn't
usually rely on tillage to control weeds.
Mulch-till is the possible exception, yet the goal is still to maintain high crop
residue levels. Generally speaking, no-tillers only use tillage to handle weed
escapes or out-of-control populations but most rely on herbicides and a sound
scouting program.
Seven-point management program
Many successful no-tillers find that herbicide costs generally decrease and
become competitive with conventional tillage systems in three to five years.
The continued development of new herbicides and high-residue crop cultivators
has also made weed management for conservation tillage more effective and
economical. However, successful weed management still requires a high level of
skill.
To achieve this level of minimal economic input and practical skills, most top
no-tillers follow a seven-point management program for weed control:
1. Learn to accurately identify
weeds.
2. Scout fields regularly for
known and
potential weeds.
3. Use proper timing and spray
equipment for herbicide
treatments.
4. Spot spray herbaceous and
woody
perennials (particularly
for no-till).
5. Keep fence rows and field
borders
free of aggressive
weeds.
6. Distribute residue evenly
behind the
combine.
7. Read and follow the herbicide
label at
all times.
Look for weed shifts
Less tillage usually means seeds stay near the soil surface instead of being buried.
That makes it tough for large-seeded weeds (like velvetleaf and common
cocklebur) to germinate. However, small-seeded broadleaf weeds and annual
grasses can still germinate under crop residue. Often, the result with no-till is
that large-seeded weeds decline while the small-seeded varieties may increase in
number.
The one gradual change that is most challenging for no-tillers is the shift from
annual weeds to several, hard-to-control perennials. Increased woody species or
volunteer trees can become evident in some no-till systems after 7-10 years.
Table 8 lists common weeds in no-till to look for in the first 3-5 years.
|
