Pest Control in Cucurbits Using Paper Mulch and Intercropping

Pest Control in Cucurbits Using Paper Mulch and Intercropping

Summary

The purpose of this study is to measure the relative success of paper mulch and/or companion plants in controlling pest population in vine crops that are more susceptible to cucumber beetles (Acalymma vittatum), squash vine borer (Melitta curcurbitae) and squash bug (Anasa tristis).  The study design includes multiple replications with a control (no paper, no companion plant) and two possible treatments (paper mulch and/or companion plant).

Weather conditions on the farm in 2013 forced modifications to the study for the duration of the first year.  Assuming a year that is closer to seasonal norms, we anticipate returning to the original design.  Longer season vine crops were eliminated from production and were not available for the study.  In response to this, we added summer squash and zucchini to the study parameters.

Results for summer squash and zucchini showed no significant difference in production or pest presence during the trial.  A limited trial on shorter season melons and winter squash showed differences in young plant survival rates.  A very limited trial on short season watermelon showed no differences.

Objectives/Performance Targets

Wet and cool weather conditions during the growing season prevented planting of our vine crops for most of the Spring.  Our earliest planting window occured in early July, which resulted in the removal of longer season vine crops from our growing plan.  Our first planting of transplants were too old and could not be planted without significant loss due to transplant shock.  Therefore, a second planting of transplants was necessary for the shorter season vine crops.

Variably wet fields required reconfiguration that did not allow for study set up as planned for this project.  Further, the compressed time frame reduced our available resources for collecting insect presence data.  We made changes in an effort to gather some results with the hope that we could follow the research plan more thoroughly in 2014.

The following modifications were made:

1. summer squash and zucchini were added to the trial
2. long season vine crops were removed from the trial for this season only
3. the variable for companion plants was removed to allow for sufficient replication
4. pest trapping was removed in 2013, to be added back in 2014

Accomplishments/Milestones

The melon varieties were modified to focus more on the shorter season varieties on our heirloom list.  These included Minnesota Midget, Eden’s Gem and Ha’Ogen.  Some of the longer season varieties were planted with the knowledge that the time was too short for them to mature, this included Boule d’Or, Oka and Pride of Wisconsin. 

Two replications were completed using only the paper mulch treatment versus the control (no treatment).  Plant date was July 7, at least one full month after what we consider a normal ‘safe planting date’ on our farm for these crops.  We were forced to destroy the first set of transplants as they were too old to survive the process.  We did start a second set of transplants once it became obvious the first planting could not be put in soon enough.  These were at peak transplant stage when we put them into the ground.

Results were as follows:

• As expected, weed pressure was greater on the control rows.
• Plant loss on rows without the paper mulch within the first 10 days was twice as likely.
• Production numbers for all melons were very low.  80% of the production came from the treatment rows.
• Early loss could be traced to girdling by cucumber beetles.

Because of weather considerations, we do not place great significance on these results at this time.  A warmer Fall with a late frost date is the only reason we saw any production from most of these plants.  We would prefer to see a full growth season that fits into normal pest life cycles that would be experienced by these crops.  We feel that we were on the tail end of the first generation of cucumber beetles at the time of planting.

Watermelons were limited to a very short season variety (Sweet Siberian).  No differences were determined between treatment and control.

Winter Squash was limited to acorn and spaghetti squash.  Some space was given to Burgess Buttercup, but these did not have the time to mature.  Transplants, in this case, were older than desired at the point of planting.  Soil was extremely rough due to our working the soil when it was still too wet.  Despite the rough conditions, we had little trouble laying the paper with the mulch layer.  Instead, we had difficulty planting into the rough soil.

Results were as follows:

• significant early plant loss occurred in the control rows due to the rough soil
• 80% of the harvest, which was minimal, were in the treatment rows

The rough soil prevented good contact with the root balls.  Also, plants were older than normally desired when they were transplanted, thus they would be subject to more transplant shock.  The paper mulch worked as any mulch would, protecting the plants some from the winds that dried out the root balls on the unmulched plants.  All plants were drip irrigated at transplant and as needed thereafter.  However, very strong winds made it difficult for the control plants.

Harvest of the acorn and spaghetti squash were at approximately 25% the normal harvest.  Results should not be extrapolated from this season due to the extraordinary nature of the weather in 2013.

• Melon replications after transplant
• Melons on August 14

Impacts and Contributions/Outcomes

Summer squash and zucchini were not originally in the plan.  However, since our season was compressed, we were able to add them to the study.  In a typical season, we grow three to four successions of these crops, thus making it difficult to come up with replications that had enough size to be worthwhile to include in the study with the two treatment variables.  However, in 2013, our successions were compressed roughly into one, thus we were able to do reasonably sized replications.

As with other vine crops, we were forced to compost most of our first transplant trays and had to use later transplants in the field.  We were also forced to reconfigure fields to work around wet areas.  Sections that were planted into areas that were obviously affected by the moisture were removed from the study replication areas.

Results were as follows:

• no difference in plant loss was observed
• no significant difference in yield was observed for most varieties
• Golden Zucchini showed significant young plant loss in the control and minimal in the treatment areas
• weed control was better in the treatment rows early and worse late.  However, the crops were ready for termination at that point.
• control plants showed faster early growth, but did not produce any earlier than treatment rows.  The latter caught up in size at the point of first production.

• Summer Squash and Zucchini picture 1
• Zucchini off paper
• Summer Squash and Zucchinni Picture 2
• Zucchini on paper
• Zucchini /Summer Squash end of season

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