Ontario has experienced some challenging conditions. Make your forage production system more resilient. Christine O’Reilly, OMAFRA

1. Forage Production
in Adverse Weather
Christine O’Reilly
Forage and Grazing Specialist,
OMAFRA
Eastern Ontario Crops Conference
Kemptville, ON
February 12, 2019

2. All our forages are stressed
• Tough seeding year conditions
• Tough production year conditions
• Pests and diseases
• Crop management practices
How can we reduce stress in 2019?

3. Fertility
Economic response to fertilizer below:
12 ppm P
120 ppm K
High removal rates:
23 kg N/tonne DM
6.1 kg P2O5/tonne DM
23.5 kg K2O/tonne DM
2.5 kg S/tonne DMPhoto: OMAFRA Soil Fertility Handbook

4. Phosphorus and alfalfa
• P is critical for roots and
energy
• Deficiency shows as
slowed growth, spindly
plants, small dark blue-
green leaves
• Low soil P negatively
affects winter survival
Arizona College of Agricultural and Life Sciences – Cooperative Extension

5. Potassium and alfalfa
• K – critical for enzymes,
water regulation and
winter survival
• Deficiency shows as
yellow/white spots
along leaf margins
(older leaves)
• Subject to luxury
consumption

6. Sulphur and alfalfa
• High uptake and removal: >5 lbs S/ton
• Early season demand – impact of cool, wet
spring?
• Deficiency can have significant effect on yield

9. 1.6x
2.3x
2.6x

11. 2.8x
4.0x
9.5x

12. Feed your forages!

13. Without added fertility: ↓ P 3.3 ppm, ↓ K 27 ppm

14. Fertility
• Right source
• Right rate
• Right time
• Right place

15. Cutting Height
Plants need energy to regrow.
Two sources:
1. Photosynthesis (easy)
2. Draw on root reserves (harder)

16. Cutting Height
If leaves are left behind, the plant
can still photosynthesize to fuel
regrowth

17. Cutting Height
Without leaves the plant must
draw on root reserves, which is
slower and causes more stress.

18. What Does the Research Say?
Minimum height fine when no other stressors.
Species Minimum Cut Height
Alfalfa 2.5 cm (1”)
Fall = 10 cm (4”) for snow
Cool-season grasses 10 cm (4”) est.
7.5 cm (3”) prod.
Warm-season grasses 10 cm (4”)

19. What Does the Research Say?
Low cut height (alfalfa):
• ↑ yield 0.5 tons DM/acre per inch Wiersma, 2000
• ↓ quality ~4 RFV points per inchWiersma and Wiederholt, 2001
• ↑ risk of soil contamination
– 1% ↑ in ash = 1% ↓ in TDN
– Equal to delaying 1st cut by 4.5 daysBlank, Orloff, & Putnam, 2001
• Can reduce stand longevity

20. Raise the cutting height in 2019!

21. Cutting Schedule
Forage crops grow
leaves before they refill
their root reserves

22. http://extension.uga.edu/publications/detail.html?number=B1350&title=Alfalfa%20Management%20in
%20Georgia

23. What Does the Research Say?
• ↑ # of harvests = ↓ root reserves
• Persistence improves when alfalfa is cut
between 1st flower and 25% bloom Alfalfa Management
Guide, ASA
• Timing of fall harvest is
important; can ↓ spring
yields
https://aces.nmsu.edu/pubs/_a/A336/welcome.html

24. Cutting Schedule
Breaking dormancy
Forage crops rely on root
reserves for early spring growth

25. Cutting Schedule

26. What Causes Winter Kill?
• Flooding
• Ice sheeting
• Heaving
– Dries out crowns
– Breaks taproot
• Other stressors (weather, nutrient
deficiencies, harvest management, pests,
diseases)
Oxygen starvation

27. Alfalfa Stand Assessment
Plant Count Method (per ft2)
Stand Age Good Stand Consider
Replacement
Seeding Year 25-40 <15
1st year >12 <8
2nd year >8 <5
3rd year >6 <4
4th year or older >4 <3

28. Source: Undersander and Cosgrove, 2007

29. Photo: Scott Banks

30. Scouting Alfalfa
Plant Counts
& Root
Health
Stem Counts
Weekly Field
Walks
Pest-specific
Scouting
Assess Feed
Quality
Plan Next
Crop
Plant Counts
P&K
Application
Spring Summer
FallWinter

31. Scouting Alfalfa

32. Production Insurance
• Forage Rainfall Plan
• Forage New Seeding Plan
• Silage Corn
• Cereal Silage
1-888-247-4999

33. Things You Can Do:
• Feed the crop
• Raise the cutter bar
• Adjust harvest timing
• Timely termination (assess the stand annually)
• Scout during the growing season
• Manage risk with insurance

34. Mental Health Helpline
1-866-531-2600

35. Thank You
Christine O’Reilly
Forage and Grazing Specialist
christine.oreilly@ontario.ca
705-324-5855
Twitter: @OReilly_Ag
www.fieldcropnews.com