Trees and Shadows

Last fall and this past spring have motivated me to pay closer attention to tree's surrounding certain greens and the impact their shadows have on turf growth. The benefits of adequate sun in the fall include the typical increased air circulation and faster drying of tissue surfaces to help limit disease development. Another very important aspect of fall sun relates to the storing of carbohydrates (CHO) within the plant needed for overwintering and growth in the spring. As mentioned before, the growth habit of turf in the fall changes because of cooler temperatures and shorter days. These changes signal the plant to slow vertical growth and direct energy toward roots and the creation and storage of CHO's. The more light/energy available to a plant during the fall the more CHO's it can make and store which will help in winter survival and spring start up.
Good sun exposure in the early spring obviously helps in speeding the melt of snow and ice from the previous winter as well as warming up the soil quicker to increase plant and microbial activity.
The shade created by trees has many other physiological impacts on turf grass (low density, spindly and succulent growth, and poor root density) not to mention the direct competition trees pose to available resources for plant growth (light, water, and nutrients). Take a look and the following before and afters and see how selective tree removal can significantly increase available light and, hopefully, increase the health and, therefore, the playability of these surfaces.

8 Green Before

8 Green After

7 Green
Before and After

4 Green
Before and After

Removing trees is not the only maintenance practice we do to control their interference with growing turf. I've talked about root pruning before (November 3rd post in 2009) as it relates to cart paths. We also root prune around greens to limit root encroachment under greens. Kinda a boring picture but here it is.

Root Pruning Trench on 8G

Week of Oct 17 -24

We continue with our fall maintenance and prep for winter. Aside from the tree removal for pine beetle (previous post) and aerating greens with the deep tine aerator, we have begun our winter disease prevention program. Right now we are in better shape (health and treatment wise) than last year. Temperatures have been in a nice range with overnight lows only moderately below zero (versus 10 to 15 below zero last fall) and day time highs anywhere from +5 to +12 C. We require 2 more preventative sprays on the greens to properly preparing them for winter.

Applying Snow Mould
Treatment on 12 Fairway

The funny thing about preventative sprays is the timing. An application needs to be before conditions are right for disease to fully develop but not so soon that you risk the treatment loosing its potency. Two of the green sprays need to be done while the turf is still able to absorb the treatment; i.e. still growing/photosynthesising. The recommendations for the third application is to apply just before the first permanent snow cover. The "just before the first permanent snow cover" is the weird part. Weather forecasts, historical averages, and my "spidey sense" are the only tools I have to decide when to time that last spray.

One problem with spraying too early is the affect moisture has on spray efficacy. The more a treatment is exposed to rain events or snow melt (with respect to a contact fungicide) the less effective is its control. Aside from rain, UV light can also lessen fungicide effectiveness as a result of UV degradation. One more thing: fungicides have recommended spray intervals that range from 7 to 28 days depending on environmental conditions and disease severity. Snow cover obviously limits re-applying so, ideally, you would want to be at the beginning of the time line with respect to the spray interval when the snow does come.

We can spray all 18 greens with just over one tank so it only takes 3 to 4 hours to finish. When it comes to treating the rest of the golf course we need another 10 tanks which, when you throw in frost delays and the time needed to have spray dry on the leaf, can take up to 5 days to complete the 10 sprays required.

Pine Beetle

Blue Dots are Old Infections
Red X's are Infections for 2010
Updated 10/25/10
(click on picture for better view)

The past couple weeks I've been out marking trees that have been attacked by the pine beetle, same as last year (see "Typical Fall Work" 11/13/09).

Pitch Tubes on Lodge Pole
are Signs on Beetle Attack

Right now we have close to 57 green attack trees to remove. (Green attack refers to living pine trees that were attacked this season and are infected with the beetle now. Red attack refers to dead pine trees from previous seasons that no longer contain the beetle but still have their needles. Greys are dead standing trees with all their needles fallen off. More reading and info at: http://www.rdno.ca/pine_beetle/index.php and http://www.for.gov.bc.ca/hfp/mountain_pine_beetle/bbbrochure.htm)

Infected trees will be cut and processed (burning or milling) to kill the overwintering beetle/larvae. We monitor previous infections sites and walk the entire property (including the land owned by the golf club near the river) looking for new infection sites. A point of interest this year is the unfortunate circumstance of finding more Ponderosa hits this year. We have found infected Ponderosa's in the past but they have been small trees. This year all the new hits have been on large trees. If there is any good news all but one of the infected Ponderosa's are located in the deep rough.

Winterizing the Irrigation System

One of the most important activities we do every fall is winterizing the irrigation system. Under your feet is almost 8 miles of plastic pipe that, on average, is only 24 inches deep. The shallow depth means the water inside the pipe will freeze and shatter the pipe if it is not expelled before winter. Draining the system through low points eliminates some of the water but not all of it. To understand why gravity draining is only of a partial help an explanation of how the irrigation system works might help.

Without going into too much detail, the irrigation system at KGC is a hodge-podge of control methods and piping schemes. The front nine is a "block system" which is best described as a constantly pressurized mainline that supplies a number of laterals irrigation lines in which a single valve controls multiple sprinklers. The laterals are only pressurized when the valve opens and the sprinkler heads are running. The back nine is a "looped system". In this type of system smaller pipe feeds off of a larger mainline at two points (usually at the start and end of a fairway). Each sprinkler heads has a valve and can operate on its own. Water is supplied to each head by the smaller looped line which is constantly pressurized.

The valves in both the front and back hold water and are not drained by gravity alone. Even a little water left at the base of a sprinkler valve can destroy a head. The following picture shows an irrigation head where the ice that formed within the valve at the base of the sprinkler split the casing top from bottom. The interesting part of the picture is how little ice was needed to damage the sprinkler pot.

Damaged Pot

The only way we have to remove unwanted water from the irrigation system is to use compressed air. We use a compressor that able to generate 750 cubic feet/minute (cfm) of air. As a point of reference, a small portable compressor used for air nailers can run up to 2.5 - 5 cfm. We rent a compressor locally and use it for 2 days. We close nine holes at a time for convenience and safety. It takes a full 8 to 10 hour day to completely blow the back nine and only a 6 hour day for the front. This relates mostly to the different control systems we have on each nine ( see April 15th posting for brief explanation of control systems at KGC).

Mixture of Air and Water Being
Forced out Sprinklers

Generally, we have pretty good success with little or no damage the following spring.

The clubhouse, on course bathrooms, snack shack, river pumphouse, and reservoir pumphouse all have to be winterized as well but for those we use a smaller compressor and R.V. anti-freeze to keep the fixtures from freezing. There have been years, like last year for example, where the cold came early and hard. I seemed to have misplaced the pictures I took but the damage last year included frozen control satellites, burst irrigation pipes, frozen valves, and split plumbing fixtures. At this point in time we seem to be ahead of last year with respect to "irrigation winterizing", that is. Hopefully, that hold true for all other processes we have yet to complete!

The Down Hill Slide.....and Now the Work Begins!

Starting a far back as the first week of September we began our fall aeration program. This years weather and staffing constraints caused us to shuffle the aeration schedule around a bit but we are now on the final leg. Properly timed fall aeration (ample recovery time) can be a real benefit for the fall health of the turf. Usually, a season of play and maintenance cause the soil conditions to be less than optimal for growing healthy turf (see July 8th posting for more aerating info). Aerating will decrease compaction and result in better air exchange within the root zone. In conjunction with the increased height of cut and the turfs growth habit in the fall the benefits of aerating will encourage root development and carbohydrate storage for overwintering.

We started first with the tees. There is a little bit more of a B.S. factor for tees and, as a result, we are a little less concerned about impacting playability and pulled a fairly large core. We top dress the tee's with recycled aerating cores from our spring greens aeration. That is one of the good things about being an old Poa golf course; you can recycle things like aeration cores and not worrying about spreading Poa seeds since it is everywhere already!

For the greens this time out it was all about the core. I was too scattered brained to take any pictures but we used a 3/8 tines on 1.5x2 spacing with an extra tine every second row resulting in a 1.5x1.5 spacing for those rows. Sounds confusing but all I'm really trying to say is we had more and bigger holes than the last time we pulled cores (again, see July 8th. FYI the spacing I commented on in that post was incorrect. It should read 1.5x2 spacing). The end result was a very large volume of material and more open holes for air exchange.

The past couple weeks have seen us pick away a aerating the fairways. We use slightly different aeration equipment for large area such as fairways that is best explained as a hollow aerating tines on rotating drums.

Pulling a core with the Fairway aerator

This style of aeration is beneficial for its speed and simplicity. It does pull a core to remove thatch and allows increase air and water exchange but offers little in terms of compaction relief. The good thing about the recent weather leading up to the nice spell we are experiencing now is the rain made the ground nice and soft which is allowing us to pull a good 3 to 4 inch core. A perfect world would have us using the same style aerator we use on the greens but the reality of our fairway root zone (or should I say "rock zone") limits our options to a fairly robust aerator such as the one pictured. We don't have the equipment or available material to top dress the fairways but we select certain areas and do a very limited overseed/top dress. I am always on the look out for a good, cheap source of sand since top dressing the fairways would be very beneficial for health and playability. No luck so far.