Alfalfa weevil, grasshoppers cause for concern, rainfall offers some crop relief

Manitoba Crop Report and Crop Weather report for July 9

Southwest Region

Normal to above normal temperature in past week has benefitted the crop development. Rainfall was very spotty and in thundershowers with varied amounts. Deloraine (20mm), Shoal Lake (16mm) but most of areas in other parts of the region got 5 to 15mm range. Crops like soybean, corn and sunflower can use significant moisture at this stage. Cereals and canola needing moisture in their reproductive stages. Growing degree days are still below than normal in most of the region.

Winter cereals are starting to ripen. Most of Fall Rye fields are turning very fast. Crops are looking good but yield potential is not very promising due to shortage of moisture at early and reproductive stages of the crop.

Peas are flowering with some early seeded crops forming pods. There are no issues reported in peas as most of the moisture is very timely. Some odd fields, which have spots of excess moisture showing disease signs in peas.

Eighty per cent of spring cereals are heading and several producers are using fungicide spray for the Fusarium Head Blight risk. Overall crop is looking very good some areas are in need of moisture. Some fungicide is being applied to spring wheat for the elevated FHB risk, and protection from leaf disease. Timely rains and amounts have allowed for maximum yield potential. Generally low leaf disease pressure at this moment. Barley appears to be the best cereal for stands this year.

Canola is very stagey, with some fields, which were not reseeded, are full flowering. Producers are planning for sclerotinia fungicide applications, as crop is very thick. There are also fields that are not thick and tall with many empty patches due to cutworm damage, that are also starting to flower. The third scenario are reseeded fields (due to dry weather and flea beetle damage) that are cabbaging to bolting s and are coming along well. There are some weed issues in thin/patchy fields.

Soybean crop needs a lot of heat at this stage. 50 per cent crop is at V5 to V6 stage. 50 per cent crop is at R1 stage as some early seeded fields are starting to flowering. Producers are doing the second pass of herbicide if needed. Good nodulation is happening in most of the fields as crop is benefitting from recent moisture.

Early seed flax is in full bloom. Stands look tall and full, low disease pressure.

Sunflower at R1 stage and about 1 m tall. Low insect pressure so far. Stagey emergence early in spring giving rise to plants behind in stages, perhaps V4 to V8.

Corn is 0.5 to 1.2 m tall depending on stage. Stages range from V8 to V12. Patchy development in field areas, some with limited nutrients with nitrogen and sulfur symptoms.

Recent rainfall has greened most pastures areas, but overall productivity is below average. Grassland hay is average to below average and is fully headed out, however alfalfa/sweet clover stands show some promise for average to above average yield. Alfalfa in full flower stage. Haying has begun in the area with only a few fields cut and some baling has occurred.

Recent rainfall has improved the quantity of the first cut. Yields are below average however not as low as first expected. Quality is going to vary as some producers received rain over the last week on cut hay. Rainfall is also helping pastures that had not been overgrazed and producers using a rotational grazing system will definitely benefit from rain. Dugouts are about 60 to 70 per cent full.

Northwest Region

Generally, good growing conditions continuedNorthwest region last week. Daytime temperatures were close to 30 C, and welcome rain showers fell through most of the region. Rainfall amounts ranged from 9 mm in the Dauphin/Ste. Rose area; Bowsman area 36- 75mm; Swan River/Grandview and Laurier 25mm and around The Pas 13 mm. These showers have helped crops to advance, however, the driest parts of the region received the least amount of rain and crops in those areas are showing the effects of lack of moisture. Soil moisture conditions around Dauphin/Ste. Rose area continue to be short; Swan River and Roblin areas are 90 per cent adequate, soils in The Pas are 100 per cent adequate.
There was good progress on the growth of the crop in the region in areas with adequate precipitation while areas with limited moisture are showing symptoms of drought stress. The canola crop advanced this week with 75 per cent of the crop flowering; the later seeded canola is now bolting. Approximately 80 to 90 per cent of spring cereals are heading out. Field peas in the region are in the vegetative stage with 40 per cent of the crop flowering. Soybeans are beginning to flower (R1 stage).

Diamondback moth larvae are actively feeding in some canola fields around Swan River and producers are encouraged to scout their fields for these pests. Thistle caterpillars have been observed in soybeans and although most are nearly past the larval stage, smaller larvae are still in field and continue to feed. Bertha Armyworm moths are showing up in traps throughout the region. While still at “low risk”, numbers are nearing the “uncertain” range in both Bowsman and Ste. Rose areas. Generally, crops in the Northwest region are rated as average although drier parts of the region are rating crops as below average.

Haying has started throughout the Northwest, with yields 50 per cent of normal. Grasshoppers and Alfalfa Weevil are present on many pastures or alfalfa fields. Continued dry conditions exist throughout much of the region, heightening the need for moisture for continued growth on pastures and hope for an improved second cut of alfalfa. Without desperately needed rainfall pasture, growth will be minimal to none in the next few weeks. Dugouts are being reported to be 40 to 50 per cent of capacity with up to 70 per cent in the northern part of the Northwest region. Many cattle herds have been moved to hay fields and some annual crops for grazing. Silage yields are still looking favorable at this point.

Central Region

Seasonal temperatures prevailed for the week benefitting crop growth and development. A localized rain system brought moderate precipitation to the southern part of the region with amounts between 5 to 12 mm. Severe thunderstorm occurred Monday over the eastern Red River Valley and into the Eastern region, with rainfall up to 20 mm at Morris and 61 mm at Brunkild, along with some hail. Aubigny area reportedly received 125 mm during this same storm system. Some of the central part and the northern parts of the region remain wanting for rain. Soil moisture conditions have improved from those recent rainfall events but soils have been able to absorb much of the moisture received so far. Overall, rainfall received since May 1st remains below the long term average across the region.

Wheat, oats and barley are growing reasonably well depending on the local moisture conditions with those crops in the heading to fully headed out. Disease pressure has been low to date given the prevailing dry conditions but some foliar diseases have been noticed with the recent moisture conditions favourable for disease development especially on the western side of the region. Fungicide applications have been going on wheat at anthesis to protect against fusarium head blight. Corn growth is accelerating with the recent warmer temperatures. Staging varies from V7 to V8 leaf stage for the most advanced crops. Other fields are lagging behind and some are showing signs of moisture stress depending on the area. Second pass herbicide applications are considered complete.

A number of canola fields above the escarpment partially reseeded will have different stages of development as the season progresses. Canola is most advanced in the Red River Valley with many fields in full flower, while bolting to early flowering above the escarpment. Fungicide applications on canola are being applied to fields considered at risk for sclerotinia infection. Flax is flowering and foliar fungicides applied to fields at risk of disease development.

Sunflower is at V10 to early bud formation (R1). Potato fields are showing good growth with the recent rains and warmer conditions. Irrigation of potato and vegetable fields is occurring to maintain soil moisture and support growth. Field peas are growing well and flowering. Soybeans are blooming in half of fields in the Altona area, while areas above the escarpment still in the vegetative stage. Soybeans and edible beans are in need of water in north and central part of the Red River Valley but doing well above the escarpment. Iron deficiency chlorosis (IDC) symptoms are still noticeable in soybean fields but fading.

Fall rye fields are starting to ripen while winter wheat is in the soft dough stage.

Bertha armyworm traps are set up across the region to monitor the emergence of this canola pest over the next few weeks. Grasshoppers have been causing damage to fields in the eastern part of the Red River Valley. Grasshoppers spraying continues on fields where economic threshold has been reached.

Colorado potato beetles are active with the warmer temperatures and control measures are necessary in some fields.

Grasshoppers and alfalfa weevil are damaging forage stands.

Good progress has been made on the first cut hay crop with yields running 25 to 50 per cent of normal.The older hay fields with a higher percentage grass are short, thin and well below average for yield. Forages are very stressed due to the lack of rainfall and hay production is well below average due to dry conditions. Pasture growth and hay yields are best in the south-central part of the region and are yielding better than expected. Pastures are starting to brown off and regrowth is minimal to non-existent.

Producers are expressing concern with the poor hay crop and feed shortages. Straw will be needed and baled as a source of roughage. Culling of cows and reducing herd sizes has begun and will increase if conditions remain dry. Livestock water supplies are becoming low, negatively affecting water quality.

Eastern Region

Rainfall accumulations across the Eastern region ranged from zero to >20 mm, however most districts received trace amounts due to isolated thunderstorms. Rainfall accumulations did not make a difference to soil moisture status and crops in some fields were starting to show early signs of moisture stress, particularly in the mid-day heat. Soil moisture conditions on cropland across the region were rated as adequate on 85 per cent of acres with the balance being short to very short. Daytime and nighttime temperatures were normal to above normal for the majority of last week.

Plant growth continued at a rapid pace, particularly for warm season crops. Iron-deficiency chlorosis in soybeans has largely disappeared, but with significant varietal difference noted. Producers want to see significant rainfall as soon as possible to limit loss of yield potential in cool season crops and to allow the establishment of high yield potential in warm season crops. Crop condition is generally good but has started to deteriorate and will accelerate if rainfall does not arrive next week.

Herbicide applications were virtually complete for all crops across the region. Fusarium head blight (FHB) fungicides on spring cereals were about 90 per cent complete across the region for those fields slated for a treatment. Given the dry weather, some producers chose not to apply FHB fungicides on spring cereals this year. Canola fungicides for sclerotinia were about 80 per cent complete. Producers were monitoring their canola crop canopy conditions, flowering progress and weather forecasts carefully to determine whether fungicide applications for sclerotinia would continue. It is expected that some fields will not be sprayed this year. Some insecticide applications to control grasshoppers in cereals has occurred, with many fields being scouted.

Spring cereals were headed out and flowering this past week. Corn growth stage ranged from V8 to V10, while soybeans ranged from V6 (6th trifoliate) to most crops being in R1 (beginning bloom). Sunflower growth stage was R1 with canola fields ranging from 5 per cent bloom to being past 50 per cent flower. Spring cereals and canola have struggled with crop uniformity for flowering stages.

Hay cutting has caused significant migrations of grasshoppers into neighboring annual crop fields which sometimes resulted in insecticide spraying. In cereals, some combination applications of insecticide for grasshopper control and FHB fungicide have occurred. Painted Lady Butterfly larvae (thistle caterpillar) were noted in a few soybean fields but were not a cause of concern. Cloverworm and diamondback moth larvae in canola, and aphids in cereals are all below threshold levels. Overall, crops appear to be starting to lose their condition and possibly some yield potential.


Highs for daytime temperatures ranged from 29 to 31 C this past week. Minimum overnight temperatures dropped, ranging from 1.4 to 7.5 C. Crop growth has improved with warmer temperatures. Trace rainfall only for most of the region, although thundershower accumulations were higher. A narrow band in the north Interlake, including Eriksdale, Poplarfield and over to Riverton received as much as 20 to 40 mm. Any precipitation is welcome and all areas, particularly the north and east part of the region, remain short for moisture. Precipitation continues to be below 50 per cent of normal. Some reseeding is taking place on fields that hadn’t germinated, in the northwest. Timely rains are needed as crops just barely hang on from shower to shower. Topsoil moisture is currently adequate for 50 per cent of the crops and short to very short for the remaining acres.

All crops are shorter than normal, and majority of crops have suffered from dry and cold conditions, sometimes frost and in many cases, insect pressure. Peas and flax have fairly even stands and are progressing well. Flax is flowering, most fields are on the short side, some fungicide applied for pasmo. Peas also shorter than normal and in full flower/podding; most fungicide applications are complete. Sunflowers are growing well. Canola is starting to fill in, many fields are at full flower. Stands are on the thin side, and in some cases very stagey, due to earlier stresses including frost and insects. Fungicide applications are taking place, but widespread applications will not occur due to dry conditions. Most soybeans are at V3-R1; majority of fields are short. As with all crops, stands are stagey due to dry and cold conditions. A bit of interveinal chlorosis has been noted, but minimal for most. Some yellowing due to high salinity. Second pass herbicide applications complete for most. Nodulation is generally reported as excellent. Most corn – both grain and silage – has improved in both growth and colour, although leaf curling due to persistent dry is evident in some fields. In the driest areas, silage corn is yellowing/browning. Cereals have rapidly advanced, and most have headed.

Most fungicide applications for fusarium head blight are complete; acres treated are much lower than normal due to dry conditions. Applications won’t be made in the driest areas, where crop potential doesn’t warrant treatment. Crops are drying out on sandy ridges, evident in cereals and canola. Some oat and barley acres will remain flexible, going as grain or greenfeed as necessary. Barley silage will be cut in the next week or two, followed by oat/pea silage. Millet was seeded due to concern about hay and pasture. New hay acres have been seeded, older stands have been renovated. Some alfalfa was terminated after first cut, and seeded to barley or oats for greenfeed; not enough moisture to date to for germination. Alfalfa is flowering, and leafcutter bees are going out.

Cutworm activity has tapered off; in some areas, damage is worse than first expected. Grasshoppers are being monitored closely, and some headlands and fields have received insecticide application. Damage is being done on pastures as well, making poor conditions worse. Diamondback moth numbers have increased since the beginning of June; monitoring for larval feeding continues. Larvae can be found; many have matured to the cocoon stage. Feeding injury is currently not a concern; the next generation will be watched closely. Bertha armyworm counts are low. Some thistle caterpillar reported in soybeans.

Forage availability is a big concern for the region, especially as many producers have exhausted their surplus feed supplies. Without rain, some producers predict they will be short of pasture by mid-July, and feed shortages will be an issue. There is little regrowth on grazed pasture due to low rainfall, and many are just hanging on. Grasses have headed prematurely and are drying down. Surface dryness is to the point where fires are starting upon hay cutting, and burning across hay fields through standing grass. First cut hay continues, with variable quality. Yields are extremely variable depending on moisture levels; estimated yields are pegged at less than half of average production.

Second cut will be limited, if any, due to lack of regrowth. Some hay has been cut early due to poor pasture conditions and lack of feed supplies. North Interlake reports cutting to get in front of alfalfa weevil and grasshopper injury. As crops are short, availability of cereal straw will be limited. Pastures are rated as fair (30 per cent), poor (30 per cent) to very poor (40 per cent). Hay fields rated as fair (40 per cent), poor (20 per cent) to very poor (30 per cent). Topsoil moisture for hay and pasture is rated as 70 per cent short and 30 per cent very short.

Dugout levels are quite variable; all are declining, some are dry. Water quality is a concern in low dugouts. Water supply is rated as 70 per cent adequate, but significant rain is needed for replenishment. Water hauling to pasture troughs is occurring in north Interlake. Concern over adequate supply is increasing with continued dry conditions.

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