Ontario Field Crop Report
Forage Crops Seasonal Summary

Table of Contents

  1. Extensive Alfalfa Winterkill In Eastern Ontario
  2. New Seedings
  3. First Cut Yields and Quality
  4. Second and Third Cuts
  5. Hay Inventories Tight In Some Areas
  6. Insects
  7. Pastures
  8. Critical Fall Harvest Period
  9. Corn Silage
  10. Challenges for 2006

Extensive Alfalfa Winterkill In Eastern Ontario

Significant numbers of alfalfa stands in eastern Ontario suffered severe winterkill. The most affected area extended from Brockville to the Quebec border and up into some of Renfrew County (340,000 acres of alfalfa mixtures). Upwards of 70-80% of the alfalfa was reported as heavily damaged in this area, including many fields in the Ottawa Valley that were totally destroyed. Orchardgrass was also winterkilled. There was also a much higher than normal level of alfalfa winterkill in the east-central Ontario area (Toronto to Kingston).

Poor winter hardening was the result of warm fall temperatures and a late frost, followed by wet weather and saturated soils in December 2004. Extremely cold weather with little snow cover in early January likely resulted in extensive freezing damage. Other contributing factors included extensive harvesting during the 2004 Critical Fall Harvest Period (the forage was needed and the weather was good), some ice sheeting, alfalfa root disease complexes and crown heaving on heavier soils. Diseased older stands on flat, clay soil types were most susceptible to damage. New seedings that had experienced high levels of potato leafhopper damage during 2004 also appeared more likely to be affected.

In the areas where alfalfa winterkill occurred, there was extensive new alfalfa seedings (more than one-half the acreage in the east), some "patching", as well as the seeding of emergency annual forages such as cereals, cereal-pea mixtures, corn silage or sorghums.

New Seedings

Winter survival of 2004 summer seedings was poor where extended dry conditions in August and September reduced or delayed emergence going into the fall.

With good seeding conditions in April and early May of this year, most new forage seedings were in the ground in good time. Rainfall was variable across the province with some areas very dry in June and July while other areas received adequate moisture. Where rainfall was sparse, the success of new forage seedings was compromised. With hot, dry weather and uneven emergence, many new alfalfa seedings were not sprayed for broadleaf weed control for fear of suppressing alfalfa growth resulting in some severe weed infestations. Annual grass pressures were also high in many new seedings. This may have reduced stands further and these fields should be checked early in spring for stand and vigour. In addition, many new seedings underseeded to cereal nurse crops were affected by lack of moisture, with a negative impact on stand establishment.

A considerable acreage of summer seeding occurred, but in the areas that remained dry into August, many farmers cancelled their plans for summer forage seedings. Delayed emergence and reduced stand establishment of summer seedings occurred where drier weather continued into September.

First Cut Yields and Quality

A combination of cool spring temperatures followed by extremely dry weather in June reduced forage yields in some parts of the province. The relative growth of alfalfa and grass was very regional. With the many cool days, cold nights and reduced Growing Degree Days (GDD) in April and May, the growth and development of alfalfa was significantly behind normal in much of the province at the end of May. In some of the lower CHU areas, the alfalfa growing points may have been damaged by heavy frosts received in early May, and the subsequent auxiliary bud development may have resulted in delayed growth. The cool weather slowed the growth and development of the legumes much more than the grasses, which were closer to normal. The opposite appeared to be true on some of the lighter soils in the southwest, where the alfalfa got a head start with the warm early April temperatures.

This resulted in many mixed stands having a higher proportion of grasses and the grasses being more mature relative to the legumes at harvest. Alfalfa fibre levels were higher than normal based on stage of development.

Optimum harvest dates of first cut "dairy quality" straight alfalfa were typically a week or 10 days later than normal. Yields of early cut alfalfa haylage were generally reduced, but forage quality was excellent. However, with the extreme heat beginning the first of June, the crop matured very rapidly, increasing yields, but forage quality dropped quickly and dramatically. Later cut forage yields were extremely variable across the province, depending on localized rainfall.

Laboratory analysis of early harvested first cut alfalfa (May) found high quality with high CP and low fibre (NDF), but later cut alfalfa was much poorer. Many samples of mixed stands of alfalfa and grass had higher than normal NDF and lower CP levels.

The dry June weather did provide excellent conditions for making dry hay. Inventories of "horse quality" hay (no rain damage or dust) are much greater than last year. With the good conditions for making dry hay, the need for propionic acid application or making baleage was reduced. The exception was in some parts of eastern Ontario which received excess rainfall in June.

Second and Third Cuts

Second and third cut yields were also extremely variable across the province, depending on rainfall in localized areas. In dry areas fields where first cut was harvested late had very little regrowth. Some areas reported first cut yields to be half the normal levels and almost no second cut. Many pastures entered the "summer slump" period early and required supplementation with hay that was in short supply.

Hay Inventories Tight In Some Areas

Hay inventories are reduced in much of the cow-calf areas, including northern Bruce-Grey, Simcoe, Durham, Kawartha Lakes, Peterborough, Quinte, Renfrew, Manitoulin and Algoma. Tight hay supplies in these areas have resulted in higher hay prices. Many of the affected cow-calf producers either sold some cattle in early fall (with improved prices), or used alternate forages such as corn silage (in areas where that was an option).


Some alfalfa weevil was reported at threshold levels in the southwest, but very little spraying was required. Unlike 2004, potato leafhopper levels were unexpectedly very low across the province.


Similar to hay and haylage, the "spring flush" of pasture production was also reduced due to the cool spring and dry June. When cattle were turned out according to the calendar rather than the development of the pasture, some damage occurred. Many pastures entered the "summer slump" period early and required supplementation with stored feed.

Good pasture management and rotational grazing reduced the need for feeding stored forage during the summer. Pastures recovered more quickly in the fall where cattle had been removed to a sacrifice pasture during the dry weather. Many pastures have been severely injured by continuous over-grazing in situations where livestock inventories have exceeded forage supplies, compounded by dry weather.

Critical Fall Harvest Period

With the dry September weather and a lack of first and second cut forage, considerable forage acreage was harvested during the Critical Fall Harvest Period. This may increase the risk of alfalfa winterkill. These fields should be closely monitored in spring to determine if remedial action is required. Some producers that needed feed waited for killing frost before taking the final cut.

Corn Silage

Corn silage yield and quality were variable, but generally good. Corn silage was ready to harvest in late August and early September in most areas, about three weeks ahead of normal. As the corn crop matured and dried very rapidly, some corn silage was harvested at moisture that was too low. Corn silage harvested and stored in piles or bag silos provided a good late season forage option for dairy and beef operations requiring additional forage inventories.

Challenges for 2006

Strategies To Ensure Adequate Forage Inventories During Dry Weather

Dry weather impacts pasture and forage yields and reduces forage inventories. Farmers must develop management strategies in the event of dry weather that include rotational grazing, the use of drought resistant forage species, and the use of annual forages including corn silage. For more information refer to the following website.

Managing Alfalfa Winterkill

Alfalfa winterkill continues to be a serious issue in some parts of the province, particularly in eastern Ontario. There are many contributing risk factors, including the weather, soil type, drainage, disease complex, potato leafhopper damage, variety selection, fertility, as well as the Critical Fall Harvest Period and cutting management. Options to reduce the impact of winterkill by lowering plant stress to a minimum include improved drainage and soil structure, controlling insect pressure, ensuring adequate fertility, selection of winter hardy varieties, avoiding very short cutting intervals, and respecting the Critical Fall Harvest Period.

Rotational Grazing

Changing from a continuous grazing to rotational grazing system by subdividing fields and moving livestock frequently can result in significantly more production. A rotational grazing system can double the forage production over a continuous grazing system, and reduce the amount of hay fed during the dry summer slump. Rotational grazing with 5 or 6 paddocks, 5 to 7 days grazing, and 28 to 30 days of rest works well. Even a less intensive 4 paddock, 10 days grazing, 30 day rest system can increase production over continuous grazing.

Harvest Management For Quality Dry Hay

Frequent rains and narrow haying windows resulted in reduced amounts of quality dry hay without rain damage or mould. Predicting the weather can be frustrating, but proper conditioner maintenance and adjustment, strategic windrow management and raking, and the use of propionic acid as a hay preservative, can assist producers in reducing the risk of poor quality hay.

Potato Leafhopper

Potato leafhopper (PLH) levels are frequently high in some parts of the province (such as the Lake Erie counties), resulting in significant damage, yield loss and seeding failures. New alfalfa seedings are particularly vulnerable. Potato leafhopper damage in alfalfa is frequently underestimated. More scouting of alfalfa fields needs to be done, with insecticide applied when scouting thresholds are exceeded. PLH resistant varieties should be considered in areas where PLH levels are typically high.

For more information:
Toll Free: 1-877-424-1300
E-mail: ag.info.omafra@ontario.ca