AES- Research Greenhouse Complex


| Share

Integrated Pest Management (IPM) Guideline

Using an integrated pest management (IPM) program in greenhouses at North Dakota State University will greatly decrease our chemical use, make all greenhouses safer for users, and continue to increase the level of success for all research conducted in greenhouses. All greenhouse users play an important role in the success of the IPM program at NDSU.  The three aspects of greenhouse IPM are cultural control, biological control, and chemical control.

Cultural Control            


Cultural control is the first line of defense in a successful IPM program.  Many pest problems are difficult, if not impossible to correct without first addressing sanitation within a greenhouse space. Cooperation from all greenhouse users to comply with cultural control practices will greatly reduce the need for both biological and chemical control.


Unwanted Plant Material

All unwanted plant material should be removed promptly from greenhouse rooms that do not have impervious floors.  This includes plant material growing under benches, along walkways and walls, and within planting beds.  Unwanted plant material can harbor pests between growing cycles, thus perpetuating a pest problem.  Herbicides can be used to control unwanted plant material. Herbicide applications for controlling weeds under benches may be applied by research staff with a current pesticide application license on Mondays and Thursdays starting at 3:30 p.m. after completing a pesticide application request and receiving approval from the greenhouse manager.


Greenhouse Supplies

Whenever possible, supplies should not be stored within greenhouse rooms. Greenhouse supplies include empty pots, crossing bags, rubber boots, etc.  Supplies stored in greenhouse rooms use up valuable growing space, create places for pests to reside, and are exposed to pesticide residues.  Central storage locations for greenhouse supplies should be used first before supplies are left in greenhouse rooms.  At minimum, supplies left in greenhouse rooms should be placed in sealed containers.

In the AES Greenhouse Complex, storage of supplies within greenhouse rooms is not recommended. Each greenhouse room in BSL1 (C, G, E, and F ranges) has an assigned locker for small items in the corresponding head house.  Larger items can be stored in a sealed container, labeled, and placed in one of the central storage rooms.  For BSL2 users, all supplies must be stored in the central storage room in the BSL2 area.  Any supplies stored within greenhouse rooms are subject to removal by greenhouse staff.


Storing Soil

Soil should not be stored in greenhouse rooms; this includes bags and open containers (i.e. buckets).  Most greenhouse pests reproduce in soil, and insect reproduction in stored soil cannot be controlled.  Central storage locations for soil should be utilized whenever possible.  If soil must be stored within a greenhouse room it should be in a tightly sealed container.  Field soil that has not been autoclaved is not allowed in the Dalrymple Greenhouses.  Experiments utilizing field soil will be given priority consideration in other facilities.  


Trash cans

All trash cans containing soil, plant material, and/or garbage should not be stored in greenhouse rooms. If a trash can must be in a greenhouse room for any length of time, it should be covered with a tight fitting lid and emptied daily.

Greenhouse Floors

Maintaining a clean greenhouse floor is essential for pest control and safety.  Greenhouse pests can reproduce in debris on greenhouse floors.  Floors should be kept free of debris at all times through sweeping, raking, and/or picking up plant material and soil.  Floralife Strip-It Cleaner (Sulfuric Acid) is highly effective in cleaning greenhouse floors and can be used on all surfaces including rock and gravel.  Impervious greenhouse floors should also be kept free of standing water to prevent the growth of algae.

Harvesting & Replanting

Whenever possible, it is highly recommended that a greenhouse room remain empty for a few days following harvest.  If plants that are ready for harvest are in the same room as newly planted material, insect pests will move from older to younger plants.  By breaking the “green bridge” the pest populations will be greatly reduced, if not eliminated.  The period of time between harvest and planting should be utilized to completely wash all benches, walls and floors as well as remove all unnecessary items from the room.  “Baking,” or heating a greenhouse room to eliminate pests, is not recommended as it can greatly damage greenhouse equipment.

It is the responsibility of the research group to sanitize their greenhouse space between cropping cycles. Sanitation equipment is available through the AES greenhouse if needed.  A request for sanitation services can be made with AES greenhouse staff. The hourly rate for cleaning greenhouse space will be $175 per hour, with a one hour minimum charge. The request must be made at least 3 days in advance of when the service is needed. Greenhouse sanitation at the AES Greenhouse Complex is included in the monthly rental fee; however it is the responsibility of the research group to maintain a clean space at all times.

Biological Control


Biological control methods are only effective if sound cultural control practices are being implemented. Biological control methods should also be proactive and used at the first detection of a pest. Many greenhouse complexes (especially in Europe) have reported that the use of biological controls is more effective than chemical controls, and many locations have eliminated the use of chemicals completely.  Biological controls are safer for greenhouse users; there is no required personal protective equipment (PPE), no restricted entry interval (REI), and no threat of phytotoxicity.  While biological controls are compatible with some chemicals, the goal of biological control is to be proactive in pest management and reduce the amount of chemicals applied.


Beneficial Nematodes

Steinernema feltiae is a beneficial nematode that seeks out the larval stages of fungus gnats and the adult and pupal stages of western flower thrips.  Using beneficial nematodes to control thrips has been found to be more effective than chemical in most instances.  Beneficial nematodes are especially effective when the application begins at planting time.  Since there is no threat of plant damage, the nematodes can be applied to the soil before the seeds have germinated.

Beneficial nematodes are applied to the entire plant surface, and the soil is drenched to control fungus gnats (this is called a “sprench”) using a Dosatron injection system.  The nematodes on the foliage will parasitize the adult thrips, but will only remain active while the foliage is wet.  The nematodes in the soil will remain viable as long as the soil does not dry down completely.

If any issues arise there are some chemicals that are compatible with nematodes.  Please contact greenhouse staff to include your greenhouse space on the beneficial nematode application list.

Beneficial nematode applications pose no threat to greenhouse users.  However, it is appreciated if users vacate the greenhouse room during the 5-10 minute application period.  All plant material and soil will be wetted during the application.  For optimum control of thrips, the foliage must remain wet as long as possible, thus applications will be carried out in the morning.  Plants must not be watered until the leaves have dried completely to prevent washing off beneficial nematodes. Please contact greenhouse staff when you begin crossing.  During crossing, only the soil will receive a nematode drench.  Other biological controls such as pheromone traps can act as supplemental thrips control during this time.


Pheromone Traps

Trapping Western Flower Thrips can be accomplished through the use of aggregation pheromone.  The pheromone is packaged onto rubber septa that is gradually released.  The septa is then placed onto a yellow or blue sticky trap and hung in the greenhouse near the plant canopy.  Pheromone then draws the thrips to the sticky traps.  The use of pheromone traps is highly recommended for plants during crossing or self-pollinating when bags on plant material prevent the application of other biological or chemical controls.  Pheromone traps will be placed on Wednesday mornings as needed for thrips control.


Beneficial Insects

There are a wide variety of beneficial insects that can be used to control common greenhouse pests. Beneficial insects are released by sprinkling the insects in a greenhouse room or by hanging paper sachets on and near plant material.  Many beneficial insect colonies will establish for as long as a food source is present.  It is recommended that new colonies be released every 1-2 weeks as long as the pest problem persists.  Beneficial insects release dates and locations will be recorded in Redbud.  The beneficial insects listed below will be the primary means of control.  Fact sheets regarding these insects are available upon request.

  • Neoseiulus californicusis
  • Encarsia formosa
  • Ertmocerus eremicus
  • Phytosiulus persimilis
  • Amblyseius swirskii


Sulfur Vaporizers

Sulfur vaporizers have been successfully used to control powdery mildew.  Sulfur vaporizers should be controlled by a timer and only run at night when people are not in the greenhouses.  Sulfur prills that are at least 99.5% pure and do not have an EPA number on the container are strongly recommended.  If the sulfur has an EPA number, then it is considered a pesticide and needs to be posted and recorded in that manner.


Chemical Control


The Guidelines on Pesticide Usage in NDSU Greenhouses was established to ensure safe and legal use of pesticides and promote efficient and effective control of greenhouse pests.  Recent updates to the policy are as highlighted below. 


Greenhouse staff will coordinate a weekly rotation of pesticides, primarily insecticides.  The goal is to rotate chemical mode of actions to reduce pesticide resistance.  If you would prefer to opt out of an application, you must notify greenhouse personnel via email by noon the day of the application.  You may opt out for an extended period of time or for one application, but please notify greenhouse staff when you would like applications to begin again.  For other insect or pathogen outbreaks, please contact greenhouse staff promptly so adjustments can be made to the rotation or additional applications can be planned.

Greenhouses will be sprayed on the following evenings:

    • Mondays- All Complexes
    • Thursdays- All Complexes

    The AES Greenhouse Complex closes at 3:00 pm Monday and Thursday afternoons and key card access is disabled until 7:30 am the following day for pesticide applications.  All other complexes will close at 3:30 pm.  Our goal is to complete applications by 6:00 pm, so access is available by 6:00 am the following day for products requiring a 12 hour re-entry interval.

    Granular pesticides with the active ingredient imidacloprid (Mantra or Marathon) and herbicides for controlling weeds under benches may be applied on Monday and Thursday afternoons starting at 3:30 pm by research staff if they have a current pesticide applicator license.  These applications must have prior approval from greenhouse staff.  Research staff must contact greenhouse staff when they plan to make an application, greenhouse staff will respond via email to authorize the application.  Applications at the AES Greenhouse Complex must be completed by greenhouse staff and is included in the user fees.  Research staff completing the application must provide their own personal protective equipment and are responsible for posting the room and updating the central posting board.  Research staff are responsible for completing a pesticide application request utilizing the Redbud Greenhouse Software.    

    If the application is part of an experimental treatment for research, the project group is responsible for appropriate signage and record keeping.  The appropriate signage must be displayed for the duration of the re-entry interval.  After the application is complete, it is strongly recommended to complete a record of your pesticide application in the RedBud Greenhouse Software.  If greenhouse staff does not receive a copy of your records, the North Dakota Department of Agriculture will expect the project group to provide a copy of pesticide application records during inspections.

    Greenhouse pesticides are applied using a variety of methods.  Equipment is available to apply pesticides utilizing a fogging machine or a foliar application method.  Currently most applications utilize a foliar application method and greenhouse staff will return greenhouse equipment to normal operation after the application is complete.

    The designated central posting locations are as follows for the greenhouses:

    • USDA NCSL Greenhouses- Headhouse Hallway by A range
    • USDA SES Greenhouse- Pallet racking by the greenhouse garage door
    • Lord and Burnham Greenhouses/Plant Path and Horticulture- Outside of range 8 on bulletin board
    • Lord and Burnham Greenhouses/Agronomy- Outside of room 124
    • Waldron Greenhouses- Headhouse
    • Dalrymple (AES) Greenhouses- Staff Room, A102

    A list of the last 30 days of pesticide applications, the Material Safety Data Sheets, and the contact information for the applicator is available at the central posting location.  A detailed log book of all pesticide applications is located under the applications tab in the RedBud Greenhouse Software.    

    Pesticide posters will clearly display the product applied and the time it is safe to enter the area.  After the re-entry interval has expired, it is the responsibility of the first person to enter the greenhouses to remove the pesticide application posters.  Do not allow staff to enter a room with the pesticide poster still displayed.  

    If you have an issue with a pesticide application, please contact greenhouse staff.  If greenhouse staff is not aware of the problem, they are not able to resolve the situation.  If a solution has not been reached through contacting greenhouse staff, the chair of the greenhouse committee may also be contacted.  

    Pesticide applications may only be conducted by authorized personnel.  Current personal authorized to apply pesticides in the greenhouses are the greenhouse manager and designated greenhouse staff.  Unauthorized pesticide applications may result in employee termination or loss of greenhouse space.   



    All personnel working in the greenhouses and their project leaders will undergo mandatory training on the Worker Protection Safety Standard. This training must include the location of the Material Safety Data Sheet, Central Posting Board, and include information on the NDSU greenhouse pesticide application process. The responsibility of pesticide safety resides with everyone who uses the greenhouses; however, the project leader ultimately is responsible for the actions of the personnel working on their project.

    Creative Commons License
    Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.