Conserv FS News
Spruce Diseases
CYTOSPORA CANKER
Cytospora canker, caused by the fungus Cytospora kunzei (also known as Valsa kunzei var. piceae), is the most prevalent and destructive fungal disease of Norway and Colorado blue spruce. Occasionally, Cytospora canker is found on Douglas-fir, hemlock, and larch. Susceptibility varies widely among species, but generally trees under stress or growing outside their natural range are more prone to the disease. Cytospora canker rarely affects trees less than 15 to 20 years old. Infected trees are weakened substantially, but are rarely killed.
Symptoms
The disease normally starts on the lowest branches of the tree and, over a period of several years, progresses upward. At first, needles have a purplish hue, eventually turning brown and dropping, leaving dry, brittle twigs and branches. On severely infected trees, the fungus will enter the trunk through wounds (usually where the branch meets the trunk of the tree), killing the cambium layer and leaving dead bark. This dead tissue is called a "canker." A conspicuous white resin or "pitch" covers the cankered portion of the branch or trunk, sometimes flowing several feet down the trunk of the tree. This is an important means of diagnosing Cytospora canker; however, resin flow can also be associated with other tree injuries and is not exclusively symptomatic of Cytospora canker. Within the cankered area, black, pinhead-size fruiting structures (pycnidia) of the fungus can be seen with a microscope or hand lens and are a positive sign of the disease.
Disease Cycle
The fungus survives long-term as mycelium and spores in diseased stems. The canker grows slowly, eventually circling and killing a twig or branch. The fungal spores (conidia) are the principal means by which the disease spreads to other branches, entering through bark wounds and injuries. Infections occur in cool, wet weather. Spores are dispersed by splashing rain, wind, sprinklers, pruning tools, and possibly by movement of insects and birds. Canker development is most severe in trees under stress from drought, insect damage, crowding, nutrient imbalance, and mechanical damage to branches, trunks, or roots. Symptom development becomes more common one or two years following a severe summer drought.
How do I save a tree or shrub with Cytospora canker?
Immediately remove and destroy any diseased branches. Prune only in dry weather. Between cuts, be sure to clean your pruning shears by dipping them for at least 30 seconds in a 10% bleach solution or 70% alcohol (spray disinfectants that contain at least 70% alcohol can be used). This will prevent movement of the fungus from branch to branch, or from tree to tree during pruning.
RHIZOSPHAERA NEEDLE CAST
Rhizosphaera needle cast is a common foliar disease of spruces and other conifers caused by the fungus Rhizosphaera kalkhoffii. Colorado blue spruce is particularly susceptible and can be severely damaged by this disease. Other hosts include white, black, Engelmann, Sitka, and Serbian spruce; Austrian, mugo, Eastern white, and Japanese red and black pine, as well as Douglas-fir and Siberian fir. Norway spruce is relatively resistant.
Disease Cycle
During late summer, this disease causes first year needles to appear mottled or speckled with dull yellow or reddish blotches. Later, (often the next year) infected needles on the interior of a branch turn purplish-brown (from the tips downward) and drop prematurely. Infection generally begins in spring on the needles of the lower branches soon after the needles have elongated. Symptoms spread upward and around the tree. Sometimes infection will start on branches in the middle of a tree, creating defoliation "holes" among healthy branches. Heavily infected trees can suffer severe needle loss and branches may die as they become defoliated. Trees are rarely killed by Rhizosphaera needle cast, but several years of attack will take its toll and only the current season needles may remain. In moist conditions, the fungus inside older needles produces black fruiting structures (pycnidia) that appear as distinct rows of black, pinhead-size dots. These fruiting structures emerge through needle pores (stomata), either before or after the needles have dropped. This can be seen with a hand lens or by the unaided eye. Healthy stomata appear white. The rows of black stomata are a diagnostic feature of Rhizosphaera needle cast. This disease can be frustrating because severe defoliation can occur quite rapidly and without indication that the disease is even present.
Management
Cultural: As with most fungal diseases, infection occurs in warm, wet weather. The spores of Rhizosphaera needle cast are released from spring until fall; thus, working near trees in wet weather should be avoided throughout the growing season. For all trees showing symptoms, remove (when feasible) dead branches, fallen needles, and cones under the tree to prevent further infections. Prune surrounding plants to promote better air circulation and keep plants well watered, especially in periods of drought, to alleviate stress. Water all evergreens before winter to avoid root desiccation and winter injury.
How do I save a tree or shrub with Rhizosphaera needle cast?
You can treat infected trees with fungicides containing copper (e.g., Bordeaux mixture) or chlorothalonil. These treatments will not cure existing infections, but can prevent additional infections. Apply treatments every three to four weeks during periods of wet weather. DO NOT use the same active ingredient for all treatments. Instead, alternate the use of copper and chlorothalonil to help minimize problems with fungicide-resistant strains of Rhizosphaera kalkhoffii. For fungicide treatments to be effective, you must thoroughly cover all susceptible needles. This is often difficult in large trees. Be sure to read and follow all label instructions of the fungicide(s) that you select to ensure that you use the fungicide(s) in the safest and most effective manner possible.
MOSQUITO-CONTROL SERVICE
Mosquito control can be a profitable service add-on. Everyone agrees mosquitoes are an annoying and potentially dangerous pest in the summer months. That would seem to present a big business opportunity for anyone in the business of getting rid of mosquitoes. Lawn and landscape companies that have begun offering mosquito control services are taking advantage of that broad-based demand.
Not only can mosquitoes carry diseases that afflict humans, but they also can transmit several diseases and parasites that dogs and horses are very susceptible to. These include dog heart worms, eastern equine encephalitis and West Nile virus.
There are about 200 different species of mosquitoes in the United States, which live in specific habitats, exhibit unique behaviors and bite different types of animals.
Different species of mosquitoes prefer different types of standing water in which to lay their eggs. The presence of beneficial predators such as fish and dragonfly nymphs in permanent ponds, lakes and streams help keep these bodies of water relatively free of mosquito larvae. However, portions of marshes, swamps, clogged ditches and temporary pools and puddles are all prolific mosquito breeding sites.
WHAT IS MAPLE TAR SPOT DISEASE?
Maple tar spot is a very visible problem for maple trees. It starts with small yellow spots on growing leaves, and by late summer these yellow spots expand into large black blotches that look just like tar has been dropped on the leaves. This is because a fungal pathogen in the genus Rhytisma has taken hold.
When the fungus initially infects a leaf, it causes a small 1/8-inch-wide yellow spot. As the season progresses, that spot spreads, eventually growing up to 3/4 inches wide. The spreading yellow spot also changes colors as it grows, slowly turning from a yellow-green to a deep, tarry black.
The tar spots do not emerge right away but are typically obvious by mid to late summer. By the end of September, those black spots are at full size and may even appear to be rippled or deeply grooved like fingerprints. Don’t worry, though, the fungus only attacks the leaves, leaving the rest of your maple tree alone.
The black spots are unsightly, but they do not do any harm to your trees and will be shed when the leaves fall. Unfortunately, maple tree tar spot is spread on the wind, which means that your tree can get reinfected next year if spores happen to hitch a ride on the right breeze.
Maple Tar Spot Treatment Because of the way maple tar spot disease is transmitted, complete control of maple tar spot is virtually impossible on mature trees. Prevention is the key with this disease, but if nearby trees are infected, you can’t reasonably expect to destroy this fungus without community support.
Start by raking all your maples fallen leaves and burning, bagging, or composting them to eliminate the closest source of tar spot spores. If you leave the fallen leaves on the ground until spring, the spores on them will likely reinfect the new foliage and start the cycle again. Trees that have trouble with tar spots year after year may also be struggling with excessive moisture. You will do them a great favor if you increase the grade around them to eliminate standing water and prevent moisture build-up.
Trees may require treatment, especially if other trees have had a lot of their leaf surfaces covered by tar spots in the recent past. If you’re planting a younger maple in an area prone to maple tar spot, treat tar spot by applying a fungicide, like bayleton and mancozeb, at bud break and twice again in 7- to 14-day intervals is recommended.
GRASS SEED GERMINATION
Grass seed will germinate at a wide variety of temperatures; the optimum temperatures for germination are in the table below. The temperatures listed are air temperatures which would be almost identical to that in on the surface of the soil barring radiation effects.
Realize though that optimum temperature for seed germination can vary depending on seed age, cultivar, etc. Also, the optimum germination temperature of certain species may not involve a specific temperature but a rhythmic alternation of temperatures. Additionally, the maximum and minimum temperatures for seed germination are poorly defined because of the extreme slowness of germination, especially for the minimums.
Most of our cool season grasses can germinate almost throughout the summer, so there are many other factors control the success of seeding. Poor irrigation, diseases like damping off, and weed pressure are the most common causes of seeding failures.
Optimum Temperatures for Seed Germination
| Turfgrass Species | Optimum temperatures for seed germination (degrees F) |
| Creeping Bentgrass | 59–86° |
| Annual Bluegrass | 68–86° |
| Kentucky Bluegrass | 59–86° |
| Rough Bluegrass | 68–86° |
| Tall Fescue | 68–86° |
| Red Fescue | 59–77° |
| Sheep fescue | 59–77° |
| Chewings Fescue | 69–77° |
| Perennial Ryegrass | 68–86° |
| Intermediate Ryegrass | 45° + |
2020 SEED REVIEW / 2021 OUTLOOK
In terms of seed, 2020 was a record year for many turf seed growers in the Western US. With travel being limited (or non-existent) and vacation plans canceled, homeowners focused their time, attention, and resources (money!) on improving their lawns. Garden centers had great years and grass seed was a hot commodity. As the new crop was harvested in late Summer, prices started to drift upwards as there was very little carryover from the previous crop due to the high demand. As Fall commenced, landed costs were further strained due to severe shortages in trucking, which will continue into 2021.
As we enter 2021, seed availability is extremely tight and major grasses are already sold out until new crop is harvested in late Summer/early Fall. In other cases, some growers are holding onto what limited inventory they have with the hope prices will continue to strengthen. Perennial Ryegrass & Creeping Red Fescues have seen the largest shortages, with quality (higher weed content) a major issue. In essence, demand has been outpacing supply since Spring of 2020. With all that being said, I am happy to say that we anticipated these issues in the Fall and have locked up the majority of our needs for the coming season, while upholding our high-quality standards. With over a combined 100 years of grass seed buying and knowledge in Lisle alone, rest assured we have you covered in these challenging times.
2021 Fertilizer Outlook
Urea
Crop prices running up to multi-year highs, and the strongest farmer pre-pay for fertilizer in many years, the demand for inputs has exploded. In the last 2 weeks Urea has traded up $60-$70+/ton and has continued to show strength. We are currently at a 3-year high. The last time we have seen prices this high was in 2014. We are now the highest priced Urea in the world and exporters are trying to line up vessels to ship to the U.S.A. The adage of "high prices cure high prices" is in full effect but will take time.
DAP
Phosphates are way up this year as well. Mosaic has petitioned the federal government for a Countervailing Duty Claim against Russia and Morocco for sending Phosphate here and subsidizing it. While we waited for a judgment all summer/fall, nobody would send DAP/ MAP to our country for fear of back charging the duty on previous ships that arrived. This created a shortage, and DAP has increased over $100/ton. They have now set the duty at +15% but will not have a final judgment until the end of March. When the final judgment is made, our market should return to normal imports with production and future pricing stabilizing.
Potash
Potash has been increasing this year as well. We hit multi year lows in the summer of 2020, and since then, have been on a steady climb as supply fell short. Producers shut down their mines this fall for turnaround maintenance while farmers took advantage of a late all to get in the fields. Ultimately, our country ran short with producers sold out until March causing the rise in price. These products appear to have made their move up for spring and will probably be at these current prices until we reach a more normal Supply/Demand scenario. Hopefully, that occurs sooner rather than later, but only time will tell.
INVASIVE PLANTS
Would you be surprised to learn that ornamental plants in your yard may be causing natural areas to suffer? Some of the more aggressive plants common to backyard gardens are escaping to natural areas, where they choke out other plants and begin to take over. Even if they are pruned and kept in check, their seeds are dispersed by birds, animals, and the wind.
Invasive plants and animals threaten the nation's environment and economy. In fact, the threat they pose to native plants, animals, and ecosystems is second only to habitat destruction. Nearly half the threatened or endangered species are at risk due to competition with invasive species, and combating invasive species is costing the United States nearly $125 billion each year.
In natural areas of the Chicago region, invasive plants are choking out other plants and destroying habitats. Some of the worst invasives in Illinois are purple loosestrife, Japanese and bush honeysuckles, garlic mustard, and buckthorns. "Serious invaders of natural areas are compromising the ability to preserve biodiversity," says the Garden's director of plant science and conservation, Dr. Kayri Havens.
In Illinois, the biggest offenders include buckthorn, bush honeysuckle, and garlic mustard. Other widely planted invasives include Oriental bittersweet, burning bush, and autumn olive.
C20 SOIL BUILDER
Benefits
- Increases Soil Microbial Activity
- Decreases Soil Compaction
- Increases Water Retention
- Enhances Root Growth & Proliferation
- Increases Chlorophyll Production
- Increases Photosynthesis
- Improves Survival Rate of New Plantings
- Consistent Formulation
- Predictable Results
- Multi-Year Performance
WHAT ARE BLENDED ICE MELTS, AND HOW DO THEY WORK?
In a blended ice melt product, there are four main melting granules:
- Sodium chloride,
- Potassium chloride,
- Calcium chloride
- Magnesium chloride.
The advantage of blended de-icing materials lies in the fact that they are economically priced and still have the ability to work quickly at low temperatures. In melting ice and snow, the formation of an ice melting brine is key. Brine acts much like a lighter fluid as it ignites the melting process. The specific chloride, or combination of chlorides, that is applied and the amount applied dictates the speed and efficiency of the melting process.
Blended ice melt products bring together two or all the granular chlorides, in different percentages, for an infinite number of melting formulations. All these blends have their own unique advantages and melting temperatures based upon the percentages of each chloride used. A blend containing high percentages of calcium chloride and magnesium chloride is going to react faster and work to lower temperatures. Calcium and magnesium chloride, in their purest form, react very quickly to begin the melting process.
Potassium chloride and sodium chloride are not fast-acting and take longer to activate, or in other words, take longer to form a liquid brine. Calcium chloride and magnesium chloride are hygroscopic ice melting materials. Unlike potassium and sodium, they draw heat from the air throughout the melting process, causing a quick formation of a faster, more effective brine for de-icing. Potassium and sodium chloride do not attract heat from the air; instead, they simply react chemically with the snow and ice to lower the melting temperature. This process is slower, and the brine formed is less likely to work as the temperature drops.
When used in combination, chlorides of greater power can cause a synergetic effect to increase the melting performance of less effective chlorides. When calcium and magnesium chloride form a brine, they in turn cause sodium and potassium to form a brine faster than if used alone. It is this effect that allows blended ice melts to compete in performance with many of the stronger, more expensive straight de-icers like 100% calcium chloride and 100% magnesium chloride. Blended ice melting products deliver performance at a reasonable price and without the hazardous environmental effects of using a straight de-icing product. For more information on Ice Melt products, visit www.icemeltchicago.com
FALL TASKS FOR COOL-SEASON LAWNS
As temperatures drop in late summer and early fall, cool-season grasses peak in growth. These grasses include northern favorites such as Kentucky bluegrass, perennial ryegrass and tall and fine fescues. Warm days and cool nights make fall the perfect time for establishing new grass and strengthening existing lawns. The following fall tasks help cool-season lawns flourish:
- Soil Test. Fall soil testing helps take the guesswork out of managing your lawn's soil pH and nutrition. By making recommended improvements in fall, soil amendments have extra time to complete their work and prepare your soil before spring. lawns come spring. Test healthy lawns every three to four years, but test problem areas every year.
- Fertilize. Fall fertilizing varies from your regular-season plan. With summer dormancy behind them, cool-season grasses benefit from fertilizing. A high-nitrogen fertilizer helps lawns establish vigorous roots.
- Overseed thin lawns. Fall conditions are ideal for germinating cool-season grass seed. Overseeding thin lawns pays off with thick, strong, spring grass.
- Aerate compacted soil. Compacted soil restricts root development and limits soil oxygen. Aerators correct compaction by creating openings in the soil.
- Keep watering. Actively growing, cool-season grass needs water. But as fall approaches, you can stretch out regular watering and let rainfall help. Healthy, established lawns generally need 1 inch of water, including precipitation, weekly. As growth slows, that same amount may cover 10 to 14 days, under normal conditions.
- Control weeds. With weeds still going strong in early fall. Tackle tough weeds with targeted spot treatments. Avoid newly seeded areas.
Overseeding this Autumn?
Click below to view our grass seed mixtures:
Using Indicator Plants and Growing degree days Information as Pest Management Guides
Researchers have been determining Growing degree days numbers associated with life stages of many species of pests and stages of development of various indicator plants. Informed landscape plant managers are using this information to make wise pest management decisions.
For example, years of careful observation have shown that the eastern tent caterpillar is a young larva and most vulnerable to control measures, between 100-200 growing degree days. This is also the GDD range when saucer magnolia, Magnolia x soulangiana, is in pink bud to early bloom. A landscape manager can observe the development of local saucer magnolias to pinpoint the best time to treat or remove the small eastern tent caterpillar nests.
Another example: Suppose pine needle scale has been a problem in past years and a grounds manager wants to prevent further outbreaks. By checking references such as Coincide: The Orton System of Pest Management, he or she learns that the eggs of pine needle scale hatch and first generation crawlers are most vulnerable between 200 to 350 GDD. This is also about the range that horsechestnut, Aesculus hippocastanum, blooms. When 150 GDD have accumulated, or when horsechestnut just begins to bloom, it is time to scout pines for newly hatched pine needle scale crawlers. Since the crawler stage is the most easily controlled life stage, when crawlers are observed, it is time to treat with a registered material.
Plant phenological indicators are only guidelines. Grounds managers still have to monitor pest life stages to pinpoint what is happening at each site. Likewise, specific events in insect development occur within GDD ranges, not by a specific number. Tracking GDD and phenological indicators gives a useful way of knowing when to look for a particular pest and to manage it in its most vulnerable stage. Following signals in nature helps arborists, nurserymen, and grounds managers make effective pest management decisions and minimizes the impact of their pest control applications on the environment.
Magnolia scale
Magnolia scale eggs hatch internally and the crawlers emerge from the mother insect. Crawler emergence occurs late summer into early fall. Insect life cycles are dictated by heat so emergence of crawlers will vary from year to year. On average crawler emergence occurs from late August through the end of September. This would also be the best time to treat with insecticides. The crawlers move around until they find a suitable feeding site, usually on branches, where they settle down and remain through the winter. The adult female dies after reproducing, but may remain attached to the stem for many weeks, making the population seem larger than it really is.
Damage
Scale insects have sucking mouth parts and feed on sap from the tree. They can remove large quantities of sap and can stress the host tree. Trees can usually tolerate small populations of scale. The extensive feeding by a larger population will stress the trees and often leads to yellowing of leaves and twig dieback. Over time, an untreated population of magnolia scale may lead to decline of the tree.
Excess sap is excreted by the insects as honeydew. Honeydew is sticky and will coat plant parts and often drip onto surfaces under the tree. A black fungus called sooty mold will grow on the honeydew, but does little actual damage to the plant. The sticky honeydew and black sooty mold are often noticed before the insects are seen. The honeydew may also draw other insects like ants and wasps to the tree.
Hosts
Magnolia scale will attack magnolia trees and tulip tree. Star magnolia, saucer magnolia and many magnolia hybrids are most commonly and severely affected.
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