Landscape, Ornamentals, Nursery, and Turf Edition
Seasonal updates on ornamental, nursery, and turf pests.
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Revised New Jersey Pesticide Regulations — NOW POSTED ONLINE!
Gov. Murphy to Sign Order Requiring Outdoor Face Coverings
As reported at njbiz.com Wednesday morning, NJ Governor Phil Murphy has indicated he will be signing “an executive order mandating that masks or other face coverings be worn outdoors, as the COVID-19 virus surges across the country and the transmission rate creeps up in New Jersey.”
The state currently requires the use of face coverings indoors and at many outdoor businesses, and strongly encourages their use when in crowded public spaces, such as at the beach. The new order will require that masks will have to be worn outdoors when social distancing is not possible.
There are many outdoor operations around the farm. Be sure to plan accordingly with supplies of masks/face coverings for all agricultural workers and harvesters, in addition to planning all field work with adequate space for individuals to keep socially distanced.
For more information on keeping you, your workers and your family safe, be sure to read and implement the recommendations in NJ’s “INTERIM CORONAVIRUS DISEASE 2019 (COVID-19) GUIDANCE FOR MIGRANT AND SEASONAL FARMWORKERS, THEIR EMPLOYERS, AND HOUSING PROVIDERS.”
NJDEP Notice: Delayed Processing of Applications and Other Requests Due to July COVID-19 Furloughs
Governor Signs Permit Extension Act: NJDEP Water Certifications Extended 1 Year
Governor Murphy signed The Permit Extension Act (A3919/S2346) this week, which extends certain permits during the COVID-19 emergency. Agricultural Certifications issued by the DEP are included in this extension, so any Agricultural Certification which expired on or after March 9, 2020 will be extended.
Any complete new, renewal or modification application already submitted to the DEP will continue to be reviewed and issued for the full five-year term.
Any Certification holder who received the first renewal reminder which contained the pre-filled application form does not need to do anything at this time. The DEP will forward you a new pre-filled application once the extension period is over.
“COVID-19 extension period” means the period beginning March 9, 2020 and continuing for as long as a public health emergency, pursuant to the “Emergency Health Powers Act,” P.L.2005, c.222 (C.26:13-1 et seq.), or a state of emergency, pursuant to P.L.1942, c. 251 (C.App.A.9-33 et seq.), or both, that has been declared by the Governor in response to COVID-19, is in effect.
Please be advised that annual water diversion reports were required to be submitted to the DEP by February 28, 2020 and are not extended due to the passage of this Bill. The DEP is issuing reminders to those who failed to submit this information in accordance with their Certification. Continue to log diversion amounts and submit your reports in accordance with the deadlines in your Certification.
Rutgers Cooperative Extension is working very closely with the DEP’s Bureau of Water Allocation & Well Permitting to resolve any ongoing issues and concerns. The Bureau is aware that many renewal applications are awaiting the Ag Agent review and signature. With the extension act, these renewal applications are being extended as mentioned above.
Some RCE Offices remain closed or with minimal access at this time. Call your local Rutgers Cooperative Extension office for specific information. In addition, during the month of July, staff in the NJ Department of Agriculture and the NJ DEP personnel are furloughed, and response times will be slowed, so please be patient during these challenging times.
Azalea Leafminer: A Commonly Unrecognized Azalea Pest Problem
The Azalea Leafminer (Caloptilia azaleella) produces plant symptoms that are typically subtle & can often be overlooked. Symptoms from this caterpillar can also confuse people by having both leafminer & leafroller stages. The early instar stages are leafminers, while the later instar stages are leafrollers or leaftiers. Commercial nurseries generally have more concerns with this pest, while they often receive little attention in the landscape. Although the Azalea Leafminer has 2+ generations per year, the azalea (Rhododendron genus) is the only known host of this native caterpillar having the unique one-two punch.
Azalea Leafminers: Symptom stages from 3 leafmines & a single leafroller (Photo Credit: Steven Rettke of RCE)
Prevailing landscape disease; Entomosporium Leaf Spot on woody ornamentals
Photo: Rich Buckley
It was brought to my attention this morning that many landscapers and plant professionals are concerned by a reddening and spotting discoloration condition on Photinia foliage. Most often this is caused by the fungal pathogen Entomosporium maculatum, a widespread and destructive foliar disease of woody ornamentals in the rose family (including Photinia, Indian Hawthorn, Loquat, flowering and fruiting Pear, Firethorn, Hawthorn, Juneberry, and Quince). This pathogen discolors foliage to an unsightly red, orange, and black spotting that ultimately leads to premature defoliation. The spots will eventually turn necrotic and fungal structures will be visible within those areas (little black dots).
Photo: Rich Buckley
The pathogen can be active from late winter to late fall, favoring conditions that promote humidity and reduced airflow. The pathogen survives on infected leaves (attached or dropped). Typically it takes approximately 2 weeks for symptom development to occur post infection. Therefor the heavy discoloration we are seeing right now is the culmination of multiple infection events, where protectant fungicides were not used or were used correctly.
This means that another round of infections will occur again soon in severely infected locations as the spots will give rise to a new generation of spores.
Disease management (fungicides): Ideally, protectant fungicide applications would have been initiated every 7-14 days post bud break until all leaves had matured. However, in the current situation many people will be playing catch up. Fungicide applications initiated now will not make the symptoms go away or ‘cure’ the plant, but they are required now to protect foliage from the next wave of fungal infections and reduce the overall population. In severely infected plantings, fungicide applications should be continued every 10-14 (depending on fungicide label) days throughout the remainder of the season, especially in high value plantings or in specimen blocks. If winter conditions are unseasonably warm and humid, then applications should continue accordingly. Systemic fungicides should also be considered in addition to protective and cultural control mechanisms in severe cases.
Fungicides:
ROTATE between Fungicide Resistance Action Committee (FRAC codes)
Format: [FRAC code]: Chemical name (Trade names)
- [M05]: Chlorothalonil (Daconil WS)
- [M05 + 1] Chlorothalonil + Thiophanate methyl (Spectro 90WDG)
- [1] Thiophanate methyl (Clearys 3336)
- [11] Azxystrobin (Heritage 50W)
- [3] Myclobutanil (Eagle 40W)
- [3] Propiconazole (Banner Maxx)
- [3] Triadimefon (Bayleton 50, Strike 50WDG)
- [1 + M03] Thiophanate methyl + Mancozeb (Duosan 79W)
- [M03] Mancozeb
- [M01] Copper Oxychloride + Copper Hydroxide (Badge SC, many)
IT IS CRITICAL TO ROTATE BETWEEN FRAC CODES DUE TO THE NUMBER OF POTENTIAL APPLICATIONS
Always refer to the label for allowable host crops, use-restrictions, application rates, reapplication intervals, re-entry intervals (REI), and mix compatibility information.
DISCLAIMER: Production and pesticide information on this site are for commercial operators and landscape professionals only and are NOT for home gardener use. Provided materials represent examples and do not cover all possible control scenarios. Please contact your local agent or chemical sales representative for more information.
Click here for a list of materials available to both homeowners and licensed pesticide applicators
Cultural prevention and mitigation:
- Remove leaf-litter prior to bud break. During the season remove leaf litter only when dry. Infected leaves serve as inoculum for the next season. In severely infected plantings remove and replace mulch as fungal material can be deposited within the litter. Do not use leaf blowers to remove leaf-litter (all that does is spread around the spores).
- Avoid overhead irrigation. Water moving through the canopy represents at least two dangerous plant pathogen situations; increased leaf wetness that lets pathogens infect successfully, and movement of spores (from sporulating leaves and young growth).
- Increase airflow. Like all plant diseases, any situation that increases airflow, will decrease leaf wetness. This could include pruning, decreasing the density of plants, greater spacing, and planting/rearing site selection.
- Pruning in heavily infected plants. In addition to promoting increased air flow, heavy pruning may be required to remove overwintering inoculum from the plants. This should only be done during dry conditions, preferably during plant dormancy periods.
For sample identification please contact the Plant Diagnostic Lab here at Rutgers.
Photo: Rich Buckley
For more information and tips please visit:
Controlling Entomosporium Leaf Spot on Woody Ornamentals
Photinia Leaf Spot – Prevention And Treatment Of Common Photinia Bush Diseases
Entomosporium Leaf spot of Photinia and Indian Hawthorn
Entomosporium Leaf Spot Diagnostic Guide
Timothy J. Waller, Ph.D. (twaller@njaes.rutgers.edu)
