Research
Cover Crop results for 2002
2002
Results
The
weed pressure at Muscatine was lower than that at Ames this year.
At both locations, weed pressure grew more severe as the season passed
(Figure 1). The weed pressure was
significantly higher in the cover cropped plots than the black plastic plots at
Muscatine, but this increased weed pressure did not affect yield.
Weed growth was reaped during the three weeks prior to harvest at Ames,
so we took a third set of biomass samples at this location.
The weed pressure at harvest time in Ames was significantly less in the
cover crop + nitrogen plot than in the rest of the plots, but again increased
weed pressure in the other plots did not decrease marketable yield.
In fact, the cover crop + nitrogen plots produced more cull melons and a
higher weight of cull melons than the rest of the treatments.
This may be due to a nitrogen overload, as these plots received nitrogen
from both the hairy vetch in the cover crop and the supplemented inorganic
nitrogen. Nitrogen analyses of the
weeds sampled from these plots is ongoing and should shed more lot on the
nitrogen content of amended and un-amended cover crop plots.
Overall, the hairy vetch/rye living mulch at Muscatine and at Ames did
not suppress weeds as effectively as a conventional control, but yield was not
affected. Cover cropping appears to be a successful, sustainable strategy for
weed management. We will repeat
this experiment next year to draw firmer conclusions.
Yield
(marketable and cull number and weight) of muskmelon plantings treated with a
cover crop or herbicide and/or supplemental inorganic nitrogen fertilizer (N).
|
|
Ames
|
Muscatine
|
||||||
|
|
Marketable |
Marketable Weight (lbs) |
Cull
Number
|
Cull
Weight (lbs)
|
Marketable
Number
|
Marketable
Weight (lbs)
|
Cull
Number
|
Cull
Weight (lbs)
|
|
Cover Crop + N
|
18.5
|
106.7
|
25.2 a
|
132.9 a
|
63.0
|
374.5
|
9.0
|
39.6
|
|
Cover Crop
|
11.7
|
64.1
|
9.0
b
|
44.7
b
|
63.0
|
371.3
|
8.2
|
41.8
|
|
N
|
14.7
|
82.2
|
13.2
ab
|
47.9
b
|
65.7
|
395.6
|
9.0
|
41.9
|
|
Control
|
17.0
|
92.2
|
12.7
ab
|
55.5
ab
|
64.0
|
381.5
|
8.5
|
36.7
|
|
LSD
(P<0.05)
|
-
|
-
|
15.8
|
79.0
|
-
|
-
|
-
|
-
|