Landscape and nursery
§ New invasive woodwasp – Let’s wait and see…
§ Nursery insect update
§ Spider mites in the landscape and nursery
§ Check container fertility now
§ Scouting for disease: White smut
§ Scouting for weeds: Buckhorn plantain
§ Scouting for weeds: Broadleaf plantain
Turfgrass
§ Drought stresses turf
Christmas trees and forestry
§ Christmas tree disease update
§ Christmas tree insect update
§ Gypsy moth quarantine expanded in Chicago area
Around the home
§ Spider mites benefiting from our hot dry weather
§ Oystershell scale on burning bush
§ A little woodwasp primer
Other news
§ Weather news
Next issue August 10
Deborah G. McCullough
Entomology and Forestry Depts.
An exotic woodwasp, Sirex noctilio, was recently captured in a trap in Macomb County. The larvae of this insect feed in stressed, dying or recently pine trees. Sirex noctilio has been an important pest in pine plantations in Australia, New Zealand and some South American countries. It is native to Europe, Asia and North Africa, but was discovered in New York in 2005 and in Ontario in 2006. Like many other wood-boring insects, it probably came to North America in solid wood packing material and it was likely present for several years before it was discovered.
A recent press release from the Michigan Deptpartment of Agriculture has generated some concern among residents who think they might have seen this insect. Certainly nobody wants or needs another invasive forest pest in Michigan or the United States for that matter. But there are some important aspects of the Sirex noctilio capture in Michigan we need to keep in mind before we get too excited about this capture.
First, horntails, including Sirex noctilio, are related to wasps. Horntails can look an awful lot like a wasp and many people will likely mistake the bluish-black wasps that they see around their home for a horntail.
Second, there are 23 different species or subspecies of horntails that are native to North America. Some species colonize pines or other conifer trees. Other horntail species colonize hardwood trees – beech, for example, is a common host. Virtually all horntails are some combination of brownish, yellowish or black in color and they all pretty much look alike. Even entomologists have a difficult time trying to distinguish one species from another. Native horntails are not considered a problem. Because they colonize dying or recently dead trees, they play an important role in decomposition and nutrient cycling.
In countries where Sirex noctilio is invasive, most problems have occurred in large plantations of non-native pines. The tree that was most affected was Monterey pine, a North American species that was planted in extensive plantations in places like Australia, New Zealand, Chile, Argentina and Brazil. When drought occurred, many pines became very stressed and were subsequently infested and killed by Sirex noctilio. Keep in mind, however, that when extensive monocultures of non-native pine trees are planted, an outbreak of a plant pest is not especially surprising.
Whether Sirex noctilio will become an important pest of pine in Michigan or other areas of North America is yet to be determined. We have many insect species that colonize stressed, dying or recently killed pines. Sirex woodwasps will have to interact with and compete with those native insects for that same pine resource.
In addition, we do not yet know if Sirex noctilio is established in Michigan or if the insect collected in the trap was simply dispersing from an infestation in Ontario. Wood wasps are very good fliers and it’s quite possible this particular insect originated in Ontario. Many traps were set in Michigan this year for Sirex noctilio following the identification of the infestations in Ontario last year. After horntail flight ends (late summer) and once all the horntails collected from traps or trap trees have been identified, we’ll have a much better idea of whether Sirex noctilio is actually established in Michigan. Forest entomologists, resource managers and regulatory officials will then meet to determine what, if anything, will be done about Sirex noctilio in Michigan. That meeting will likely occur this fall.
Another aspect worth noting is that Sirex noctilio will face native natural enemies in North America and possibly an introduced biological control. There are at least two groups of native parasitoid wasps that will attack the horntail larvae. In addition, an active biological control program was developed in Australia that makes use of parasitic nematodes. Methods have been developed to inoculate pines and introduce the nematode into Sirex noctilio populations. Research is underway in the United States to assess potential non-target effects of the nematode. If results indicate that the nematode can be safely released, the methods developed in Australia will likely be used to establish the nematode here.
There are several good web sites with information about the biology of Sirex noctilio woodwasps and photos of the insect and infested trees. A few that might be of interest include:
§ Sirex noctilio Pest Alert, USDA Forest Service:
http://na.fs.fed.us/spfo/pubs/pest_al/sirex_woodwasp/sirex_woodwasp.htm
§ USDA APHIS Sirex noctilio fact sheet:
http://www.aphis.usda.gov/plant_health/plant_pest_info/sirex/index.shtml
§ USDA Forest Service; Sirex noctilio article:
http://www.treesearch.fs.fed.us/pubs/12997
If you have an insect that you think could be Sirex noctilio, contact the MSU Plant Pest Diagnostic Clinic (517-355-4536) or your local county extension office.
Dave Smitley, Entomology
The barberry looper is a colorful caterpillar (yellow bands on sides and reddish-brown on top) with only two pairs of prolegs used to “loop” or “inch” their way when they move. This caterpillar may have two or more generations during the summer, so it can be found any time from June to September.
They feed exclusively on plants in two genera: Mahonia and Berberis. The young caterpillars may devour entire leaves. Barberry and other susceptible plants can be completely defoliated if larvae are abundant. Natural enemies usually keep the barberry looper under control, especially in landscape plantings, so it is rarely necessary to spray for them in the home landscape. However, when natural enemies are suppressed, as they sometimes are in nurseries, outbreaks may occur. Watch for caterpillar feeding damage to barberry and other susceptible plants during the summer and spray with Sevin, Decathlon, Astro or Talstar if injury levels become unacceptable.
If European chafer grubs were a problem in some fields last fall or this spring, consider treating those fields with Discus, Benefit, or Marathon or Flagship. A granular formulation is recommended for application to non-irrigated fields. These products will provide excellent grub control if applied before August 1. The only other alternative is to use Sevin, Discus or Flagship in the fall when grubs are found, but applications in the fall will not work as well.
Tempo, Decathlon and Sevin are the most effective products for spraying adult Japanese beetle. The beetles will be actively flying around and feeding on preferred plants until early September. Be prepared to repeat spraying once per week or two if beetles are abundant. Sometimes it seems like the insecticides are not working because you still see new feeding damage after spraying. This happens because beetles may feed for a little while before becoming sick from the insecticide. With thousands of new beetles landing on plants each day, a little feeding from each one may result in some plant damage even though the insecticide is working.
Tom Dudek, MSU Extension Educator
Dave Smitley, Entomology
The warm, dry weather patterns that have continued across much of Michigan have caused some outbreaks of spider mites in both the landscape and nurseries. Plants that have been reported with infestations include: arborvitae, azalea, boxwood, burning bush, dwarf alberta spruce, hemlock, sunflower, spruce, serviceberry and viburnum just to name a few. Natural control keeps mites in check in the landscape. However, homeowners may want to use one half of the percent of spray of Sunspray oil or similar refined spray oil. Applications must be made weekly. The half percent spray solution works by suffocating the mites. Good spray coverage is essential.
In nurseries, where insecticide use is more prevalent, mites can be a problem because natural enemies are not present. The best products for restoring natural control are Hexygon and Ornamite, because they kill only spider mites and not predator mites and other beneficial insects. If nurseries use either Hexygon or Sanmite, one application usually is all that’s needed. Check treated plants in two weeks. Reapply if needed. Other non-selective miticides that will control mites include: Floramite, Sanmite, Apollo, Shuttle and Kelthane (if available). When using non-selective miticides, check treated plants in five to seven days and reapply if needed according to label directions.
Dean Krauskopf
MSU Extension educator
Plants in many hanging baskets and containers are yellowing and slowing growth. This may be due to the recent high temperatures, but more likely it’s due to a lack of fertility. High temperatures and low humidity have increased watering frequency and nutrient leaching High temperatures also increase the rate of nutrient release from slow-release materials, so a product labeled for four months many only last three. This varies somewhat by product, so don’t assume that the initial application of slow-release is gone and just add more.
Using liquid fertilization at one-half the recommended rate is one option. You can increase the fertilizer concentration when you are sure high soluble salts won’t be a problem. If you do decide to add slow-release materials, make sure they are evenly distributed in the pot and no pellets touch stems or leaves. Soluble salt levels near piles of slow-release materials can be high enough to kill roots and even the salts released by one or two pellets next to an herbaceous stem or on a leaf can cause damage.
Jan Byrne
MSU Diagnostic Services
Pathogen: Entyloma polysporu.
Hosts: Aster, Echinacea, Gaillardia, Helianthus and Rudbeckia.
Symptoms: Round, white spots, up to one centimeter in diameter. Young lesions may create very faint spots. Over time, the spots turn brown and become necrotic.
Spread: Spores are formed inside the leaf tissue. As lesions mature, the leaf surface ruptures releasing the spores. Spores are wind-dispersed. A white, powdery material may be visible on the leaf surface. Spores of this fungus are not known to survive winters in the northern United States.
Management: Remove all symptomatic plants. Plants in greenhouses may need fungicide applications for good disease control. The disease is favored by cool, humid conditions; disease spread will be slow under warm, dry conditions.
Note: Of the hosts listed, Gaillardia is most susceptible. The disease has been documented on the cultivars ‘Goblin’, ‘Baby Cole’ and ‘Fanfare.’ This disease has been seen with increasing frequency in the past few years.
Photo captions: 1 Whitish, round lesions on Gaillardia foliage. D. Brown-Rytlewski, MSU .
2. Older lesions caused by white smut on Gaillardia have coalesced and are causing necrosis.
3 Dieback caused by a severe white smut infestation on a landscape planting of Gaillardia. D. Brown-Rytlewski, MSU
Steve Gower
MSU Diagnostic Services
Buckhorn plantain: Plantago lanceolata L.
Life cycle: Rosette-forming simple perennial.
Leaves: All leaves originate from a basal rosette. Cotyledons are very narrow and grass-like. Leaves are narrow, linear and elongated with parallel veins and generally smooth leaf margins. Long hairs may be present at the leaf base.
Stems: No visible aboveground stem. Semiwoody taproot present.
Flowers and fruit: Long, leafless stalks bear dense, cylinder-shaped flowering spikes and fruit. Single flowers are inconspicuous. Fruiting capsules yield two narrowly oval, brown to black, shiny seeds indented on one side.
Reproduction: Seeds and basal shoots.
Photo captions: 1. Buckhorn plantain seedling. 2. Buckhorn plantain flowering spike. 3. Buckhorn plantain rosette.
Steve Gower
MSU Diagnostic Services
Broadleaf plantain: Plantago major L.
Life cycle: Rosette-forming simple perennial.
Leaves: All leaves originate from a basal rosette. Cotyledons are long and spatula-shaped. Leaves are generally smooth and broadly to narrowly oval, with parallel veins and smooth to slightly wavy leaf margins. Leaf base tapers to a distinct petiole. Petioles are usually green but occasionally pale pink.
Stems: No visible aboveground stem. Short taproot present.
Flowers and fruit: Leafless stalks bear long, dense, cylinder-shaped flowering spikes and fruit resembling a rat tail. Single flowers are inconspicuous. Fruiting capsules yield many narrowly oval, usually glossy brown seeds.
Reproduction: Seeds.
Similar weeds: Blackseed plantain (P. rugelii Dcne.)
Differs by often having dark red to purple petioles, usually wavy leaf margins and dull dark brown to black seeds.
Photo caption: 1. Broadleaf plantain flowering spikes. 2. Broadleaf plantain seedling. 3. Broadleaf plantain rosette.
Kevin Frank
Crop & Soil Sciences
On my recent road trip from East Lansing to Madison, Wisconsin for the North Central Turfgrass Researchers meeting, I observed many things. Two field mice playing in the middle of the interstate are not long for this world. My perspective on Detroit traffic jams has changed after experiencing Chicago. A work binder hanging on for dear life on the top of a Hyundai merging onto the Dan Ryan expressway is an ominous start for someone’s work day. Murphy’s Law always holds when pulling into the shortest lane at the toll booth. Landscape turf from Michigan through Indiana, Illinois and into Wisconsin is all suffering from a lack of water.
At the research meeting, we had many discussions on water use issues and turf survival during drought periods. Depending on if you’ve been under one of the thunderstorm clouds that have sporadically passed through the area and dumped some rain, the turf you’re managing may be doing okay, or it could be a beautiful shade of brown. Many homeowners choose not to irrigate their lawn and about now the concern becomes whether or not the lawn might be suffering and possibly approaching death. For Kentucky bluegrass lawns (which are the majority of lawns in Michigan), there is usually no danger that the lawn is going to die unless water is lacking for six to eight weeks. However, there are really no hard fast numbers for predicting whether the turf will die as many other factors will come into play such as high temperatures and traffic.
Even if you are not an irrigator, it might be a good idea to give the turf a little water if the turf hasn’t received any water for a month. Apply about a 0.5 to 1.0 inch of water just to make sure the lawn makes it through this cycle of drought. The goal of this irrigation is not to turn it green, but just to prevent the turf from completely desiccating (severe drying out) and possibly death. If we continue in this dry spell, I would continue to give the turf a drink every three to four weeks.
Here are some other helpful tips for dry turf. Don’t worry about trying to control weeds right now in drought stressed turf. Just like the turf, many of these weeds are slowing down their growth and trying to control them now would be more difficult, besides they might be the only green color in your yard. For those who have irrigated and still have some green turf, avoid mowing during the heat of the afternoon. This can result in tire tracks or foot printing on the lawn that may not go away for quite a while. Mow during the cooler times of the day, early morning or in the evening after dinner. Also, maintain the highest mowing height possible. Don’t think that by mowing lower you’ll help the turf by reducing the amount of leaf area the roots have to support. Remember if the turf doesn’t have any leaves, it can’t harvest light for photosynthesis, and the result is that more energy will be spent to produce new leaf tissue. Mow high and mow in the coolest part of the day.
Jill O’Donnell, Christmas Tree ICM educator
Dennis Fulbright, Plant Pathology
Management of Lophodermia needlecast disease of Scotch and red pine, caused by the fungal pathogen Lophodermium seditiosum, is slightly different than the needlecast diseases found on Douglas fir and spruce that I have written about in other reports. This disease can kill red pine seedlings and causes browning and massive amounts of needle loss on Scotch pines. Scotch pines infected with this disease have needles with brown spots surrounded by yellow margins, yellow needles or brown needles, especially at the bottom of the tree.
Lophodermium is a severe needlecast of Scotch pine, which in some cases can cause the entire tree to brown in the spring. Even though we see the symptoms of Lophodermium in the spring, the most important time to protect trees is from the end of July through September. This is when needles are infected from spores being released by the small, shiny, football-shaped, black fruiting bodies that form on the fallen needles. The dead needles currently falling off the trees this summer (June, July, and August) will be providing the inoculum (spores) that will spread throughout the trees in your plantation or nursery. These spores will infect this year's crop of needles from August to October. And, even though you won't see the result of those infection events until next year, the fungus will stay in those healthy looking needles all winter until spring, when, again, those needles will begin the process of yellowing, browning, and dropping off. To break this disease cycle, the time to manage this disease is in late July and throughout August, even into fall, if it stays warm and moist.
To initiate control, you must begin now. Look for needle spots and brown foliage on the lower branches of 50 or more trees scattered throughout the plantation. If ten percent of the trees are infected, consider treating the entire plantation by the first week of August. To reduce Lophodermium needlecast, remove the branches of pine from cut stumps where spores are likely to be produced. Apply a registered, preventative fungicide three or four times, once every two to three weeks from late July through October. Make sure all the older pines have been removed from windbreaks near nurseries or plantations. These pines can serve as sources of fungal spores.
We see several needle rusts on conifers. These can be defined by their conifer hosts; balsam fir needle rust, pine needle rust and spruce needle rust. Spruce needle rust is showing up now in Christmas tree fields and blue spruce in the landscape. Needles have yellow bands with small yellow-orange pustules on them. Spruce needle rust overwinters on Labrador tea and leather leaf and spores from those alternate hosts are now infecting spruce trees. In July and August, yellow current-year needles with whitish-orange blisters filled with yellow spores on Colorado blue, black and white spruce will appear. This will be followed by shedding of infected needles. These alternate hosts are members of the Heath family and are found in bogs and damp thickets. Care should be taken to plant spruce away from wetlands, especially the rust susceptible Colorado blue, black and white spruce. Norway spruce is more resistant. Scouting for alternate hosts, rouging infected branches and trees and planting resistant stock can reduce the impact of many of these rust diseases.
Jill O’Donnel
Christmas Tree ICM educator
Douglas fir growers, you should be actively scouting the trees near harvest age for Cooley spruce gall adelgid. Check for white, cottony balls dotting the undersides of needles on Douglas-fir. If you look under the cottony material, you will find pale peach-colored eggs or possibly the first emerging nymphs. Eggs will hatch about 1500 - 1600 degree days base 50. In most years, this has been the last part of July. Insecticide can be applied once these eggs hatch to control nymphs that will overwinter.
On spruce, we are beginning to see the first nymphs emerging from galls. These nymphs will either continue their life cycles on blue spruce or fly to Douglas-fir to lay eggs. So if you are planning on cut off and destroy galls, you will need to do that quickly before they open and a new generation of adelgids emerges.
The second generation of crawlers should be hatching in Northern Lower Michigan and the Upper Peninsula. Research at MSU indicates that the summer generation eggs can begin hatching at roughly 1,280 GDD50 (usually early to mid- July). Hatching may continue over two to three weeks. Don't load up the sprayer as soon as you see the first scale. It's best to wait until nearly all scale eggs have hatched and many of the crawlers have settled and started to feed. The ideal timing control window is generally around 1,500 GDD50. They will go from a reddish-pink color to more of a yellowish color. This is the hyaline stage. It occurs before they start secreting the hard, white armored covering. The hyaline stage is quite vulnerable to insecticides or horticultural oil. Also, just because you see a few scales on a few trees, don't assume that an insecticide is necessary. You may not need to spray, especially if the trees are at least a year from harvest or the population is low to moderate. There are lots of natural enemies out there that will attack pine needle scale.
Mike Bryan
Michigan Dept. of Agriculture
The USDA recently expanded the federal gypsy moth quarantine in Illinois to include much of the Chicago area. Cook, DuPage, Lake and McHenry counties are now regulated in northern Illinois. This action is expected to have a positive effect for the Christmas tree and nursery industry in Michigan.
Christmas trees and nursery stock shipped to these four Illinois counties will no longer need regulatory pesticide treatments for gypsy moth, saving on operating costs as well as lessening any potential impacts on the environment. Christmas trees and nursery stock shipped through Wisconsin to the regulated Illinois counties will not need to be certified for the federal gypsy moth quarantine. However, shipments moved through northern Indiana to the regulated Illinois counties should be accompanied by a special “limited permit” because the trees will pass through two non-infested Indiana counties. All nursery stock will still need to be accompanied by a copy of the firm’s nursery license as proof that it meets state inspection requirements.
Howard Russell
MSU Diagnostic Services
We are getting lots of plant samples that show very high numbers of spider mites and severe spider mite feeding injury. We’ve seen spider mite injury on Viburnum, Astilbe, Rose, Amelanchier, Burning bush, soybeans, spruce and hemlock in the last week alone. Some samples have shown the beginning stages of injury while others show advanced stages where there is very little green tissue left on the leaves.
Spider mites have piercing/sucking mouthparts. To feed they abrade or poke the leaf surface with their pointed mouthparts and then suck up the liquid that oozes from these wounds. The affected tissue more or less dries up and the result is a yellowish stippling of the leaf or needle surface. As the feeding injury progresses, the stippled areas coalesce and the entire leaf turns a brownish color. This is often referred to as “bronzing.” This yellowing and bronzing may appear similar to other damage symptoms like drought or a nutrient deficiency, so it is always a good idea to look for evidence of the mites, which will include the mites themselves, cast skins, clear spent egg shells and viable eggs. Our own Jan Byrne proudly holds the lab record for the most severe case of spider mite injury on a broadleaf ornamental.
Spider mites are among the most common and destructive of all plant pests, especially during summers that are particularly hot and dry, like the one we are having this year. Some species are very specific and feed on only one type of host plant. Others, like the twospotted spider mite, seem to be able to feed on many plant species including weeds, vegetables, flowers, field and forage crops, brambles and other small fruits, tree fruits, greenhouse plants, and certain trees and shrubs. Spider mites feed and reproduce whenever conditions are favorable for plant growth, from early spring until late fall. Most spider mites prefer new growth. Hot weather favors rapid development and reproduction. The twospotted spider mite, for example, can go from an egg to an adult in only five days at 75ºF. The female lives two to four weeks and produces about 100-300 eggs.
Most of the time spider mite populations are kept in check by natural enemies and do not require pesticides. Occasionally, during favorable conditions that produce damaging mite populations, a miticide application may be warranted to protect the host plant from serious injury. Because of their rapid development and reproductive potential, repeated treatments at 10-day intervals may be required for some plants to bring about satisfactory control.
Howard Russell
MSU Diagnostic Services
I was so impressed with the spider mite injury on the burning bush sample we got in that I almost overlooked its severe infestation of oystershell scale. The scales were so bad on some twigs that the scale took to colonizing the midveins of some of the leaves (see photos). The Oystershell scale, Lepidosaphes ulmi (Homoptera: Diaspididae) is oyster-shaped, gray, and 0.125 of an inch long. They commonly occur on twigs and limbs of apple, lilac, maple, willow, beech, ash and some other 140 or so hosts. Heavily infested parts are killed. The winter is passed in the egg stage under the female scale. Between 40-150 small, grayish white eggs will be found under each female scale in the spring. Crawlers are active in late spring, usually two to three weeks after apple bloom. The crawlers move about for a few hours before settling on the bark and inserting their long, hair-like mouthparts to begin feeding. The formation of their waxy scale coating begins soon afterwards. There appears to be a single generation per year in Michigan.
Like other “armored” scales that overwinter in the egg stage, dormant oils applied in the spring or fall are not effective in controlling oystershell scale. “Soft” scales overwinter as exposed nymphs which are susceptible to dormant oils. Control of armored scales requires insecticides be applied at the time the crawlers are active, which for oystershell scale is in mid- June. The presence of crawlers can sometimes be determined by sharply tapping an infested twig or branch over white paper. Crawlers are often orange, brown or purple and appear as moving specks of dust. Because of their waxy protective covering, other stages of scales are not readily controlled by contact insecticides. Insecticide sprays will not reach crawlers that have settled under old scales. Besides overwintering habits, another difference between armored scales and soft scales is that the soft body of the armored scale insect can be easily separated from its scale covering (see photo). In soft scales, the body of the insect and its scale covering are firmly joined and cannot be separated.
In general, controls will be more effective if heavily infested twigs or branches are pruned out. In some cases, large sized scales can be scrubbed off with a stiff brush. Horticultural oils offer a safe alternative to traditional contact insecticides and are especially good choices for sensitive areas, such as where people will be present soon after treatment. Because of their short residual, they help to conserve beneficial species. They are very effective against both active and settled crawlers.
Howard Russell
MSU Diagnostic Services
With all the excitement surrounding the recent find of a single European woodwasp, Sirex noctilio (Hymenoptera: Siricidae) in a trap in Macomb County, I think a little lesson in woodwasp identification may be in order.
Woodwasps belong to order Hymenoptera and are related to sawflies, bees, wasps and ants. Woodwasps belong to the suborder Symphyta, which includes our numerous sawfly plant pests. Like the sawflies, woodwasps do not have constricted waists like bees, wasps and ants. The abdomen and thorax of sawflies and woodwasps are “broadly joined” (like mine is). Woodwasps or siricids are also known as horntails because they have a spear-like spine, called a cornus, at the end of their abdomens. The presence of a cornus separates siricids from the other families in the suborder Symphyta. A female woodwasp, which is more likely to be encountered by the general public, also has a long needle-like ovipositor. So, a female siricid woodwasp will have two pointy structures at the end her abdomen.
The most common woodwasp submitted to the lab over the years has been the Pigeon tremex, Tremex Columba. In fact, I think this has been the only siricid species that has been sent in for identification prior to the discovery of Sirex noctilio. See photos of the pigeon tremex at http://www.forestryimages.org/browse/subthumb.cfm?sub=2105&start=1. Recently, we got in a woodwasp known as the Whitehorned horntail, Urocerus albicornis, which is shown in the accompanying photos. It’s called the whitehorned horntail because of its white marked antennae. The antennae of Sirex noctilio are entirely black.
If you think you have found a European woodwasp and would like it identified, you can send it to Diagnostic Services and we will look at it at no charge.
Jeff
Andresen
Agricultural Meteorology
Geography
An upper air ridging feature anchored across the Great Plains region led to yet another abnormally dry week last week across most of Michigan and the Great Lakes Region (some lucky areas did receive significant rainfall, but were the exception rather than the rule). Since the end of the first week in June, precipitation deficits have grown in many areas to the two to four plus inch range, which unfortunately has also coincided with periods of greatest seasonal plant water needs. The lack of plant-available water is currently most acute across southern and interior sections of northern Lower Michigan, and across western and central sections of the Upper Peninsula.
In general, weather forecast guidance for the next couple of weeks does not suggest any major changes that would lead to meaningful relief from the dryness. On Friday, a cool front is forecast to move through the state, which will bring the best chances for rainfall during the upcoming week. Rainfall totals will generally be in the 0.25-0.50 inch category, although some locally heavier totals are possible. Areal coverage of the rainfall is expected to be greatest across southern sections of the state. Fair and dry weather is likely by late Saturday and Sunday continuing through much of the upcoming work week. A frontal system should bring a chance for significant rainfall by next weekend. Temperatures are expected to remain close to seasonal normals during the next few days, with highs ranging from the upper 70's north to mid 80's south and low temperatures from the upper 50's north to low 60's south through Friday. Temperatures will warm back to above normal levels again by early next week, with highs returning to the 80's statewide.
Further ahead, a broad ridging jet stream pattern is projected across the Upper Midwest for the next one to two weeks, which will likely lead to more warm, dry weather. Unfortunately for those in need of rain, both 6-10 day and 8-14 day outlooks, covering August 1-5 and August 3-9, call for above normal temperatures for below normal precipitation totals.