Transcript
My Turf is Stressed and So Am I Golf Industry Show – San Diego, CA 9 February 2016
Adam Moeller │Agronomist │ USGA Green Section │ Northeast Region
Winter Injury Isn’t New
Slide | 2
Types of Winter Injury 1. 2. 3. 4.
Crown hydration Direct Cold Temperature Injury Ice encasement/suffocation Desiccation
• Basic Things to Remember – Poa much more susceptible to all types of injury – Drainage and shade increase injury potential Slide | 3
Crown Hydration
Slide | 4
LT50 Cold Temperature Kill
• Poa -6°F (field 5-6°F ?) • Perennial ryegrass 5°-10° F • Poa rapidly dehardens • Kentucky bluegrass -6° - -18° F when subjected to 36-40 F for 48 hrs • Creeping bentgrass -31° F Slide | 5
Winter Injury Prevention Slide | 8
Cold Temperature Hardiness • Maximize temperature hardiness in fall • Late winter/early spring critical – Plant loses CHO’s and hardiness – Hydrates, commonly with freeze/thaws – Rapid and severe temp drop often lethal
Slide | 9
Maximizing Cold Temperature Hardiness • Eliminate shade – Improve photosynthesis – Reduce early afternoon shade (i.e. sudden drop in temps)
Slide | 10
Maximizing Cold Temperature Hardiness • Slightly raise height of cut to improve photosynthesis and produce CHO’s more efficiently • Start early (mid-October) • 0.150 inches? • Using rolling alone instead of mowing occasionally
Slide | 11
Maximizing Cold Temperature Hardiness • Fertilization should be done to stimulate and support CHO storage • Avoid excessive N in fall which would force shoot growth at the expense of CHO storage
Slide | 12
Maintain soil K ≈100 ppm
Slide | 13
Maximizing Cold Temperature Hardiness • Irrigate sparingly in fall to reduce plant hydration • Utilize programs to improve internal drainage
Slide | 14
Late Fall Topdressing • 1.5-2 cu. ft. per/M
Slide | 15
• Late Fall Deep Tine or Drill and Fill
Slide | 16
Slide | 17
Eliminate Collar Dams
Slide | 18
12 inch Sod Cut?
Slide | 19
Sand Channel Drainage
Slide | 20
• Dry wells • Connect to drainage
Slide | 21
Greens Covers – Are They The Solution? GCM October 2010
Slide | 22
Winter Protection Covers • Stabilize temps and keep water out
Slide | 23
Covering Systems • Used to prevent plant hydration and ice encasement • Types of Covers Covering systems are not always 1. 2. 3. 4. 5. Slide | 24
effective but they can improve the odds Sand topdressing for success! Permeable Impermeable alone (need dependable snowpack) Permeable + impermeable Permeable + insulation + impermeable (insulating cover system)
Impermeable Cover Challenges • When to cover? – If too early interfere with hardening. – Wait too long? Snow cover/frozen ground – After fungicide/rodent repellent treatments.
•
When to remove? – General consensus remove sooner than later
Slide | 25
Expense Labor intensive Durability Storage Potential problems during extended periods of mild mid-winter weather • Difficult to document benefits • • • • •
Image: R. Ackermann
Not All Covers Are the Same Slide | 26
Monitor Soil Temperatures
Slide | 27
Impermeable Cover System Case Study - Toronto
1. Bubble wrap insulation 2. Pipes for oxygen 3. Impermeable covers Initial investment ≈ $40,000 Annual costs ≈ $18,000 Slide | 28
“We have damage, likely 3 temps for a few weeks and 3 more short term temps. If we didn’t have the cover system it would have been much much worse”
Slide | 29
Permeable Covers
Slide | 30
Fabric Bunker Liners Under Permeable Covers
Slide | 31
Best Management Practices 1. 2. 3. 4. 5. 6. 7. 8.
Increase sunlight Raise mowing height Implement fertility programs to promote turf health Adjust surface and/or internal drainage Use windbreaks for areas prone to desiccation Apply an anti-desiccant Use cover systems if there is a history of damage Increase creeping bentgrass populations
Slide | 32
Managing Snow and Ice Call Your Regional Agronomist
Slide | 33
Slide | 34
Recovery
Slide | 35
Install a Temporary Green
Slide | 36
Irrigation • Weak turf may bounce back • Light, frequent irrigation
Slide | 38
Create a Seedbed • • • • • • •
Many options Close center core aeration Verticutting in 2-3x directions Slice seeding (e.g. Turfco Tri-Wave 40) Dimple seeding (Job-Saver tines, Blec, etc.) Combinations of above Key is seed: soil contact
Slide | 40
XYZ Country Club • • • •
Verticutting 2-3x directions 1mm blades, 1 inch spacing, 0.5 inch depth Blow the debris off and channels open Overseed, Topdress, Cover
Slide | 43
Recovery Continued • Overseed the areas with creeping bentgrass (1.25-1.5 lbs per 1,000 sq. ft.) • Add starter fertilizer (1-1.5 lbs of P per 1,000 sq. ft.) • Soluble N source (e.g. ammonium sulfate) to promote growth once soils warm • Use covers or black topdressing sand to warm the soils and hasten germination – Permeable, clear plastic, or both together – Divot mix? Slide | 44
Promoting Germination • Pre-germinate or prime seed • Warm soils • Keep moist
Slide | 45
Slide | 46
Slide | 47
Recovery Continued • Light, frequent nitrogen fertility program – Soluble quick release soluble N
• Mow conservatively – Walk-behind mower w/solid front roller – Mowing height of 0.160” – 0.200”
• Light topdressing to smooth the surface • Open based on turf health; not the golf calendar Slide | 48
Sodding • Sodding is not always the best choice • Bentgrass may not adapt well to your site Slide | 49
Adam Moeller │Agronomist │ USGA Green Section │ Northeast Region
