This article is based on the experience of the author, using various types of turf maintenance machinery and turf growing techniques. Over 25 years, he has been working closely with clients of the farming business and horticultural pursuit.
The aim of this article is to arouse interest, promote the idea of turf maintenance schedules and improve the understanding of the general principles involved in turf maintenance industry.
‘Technical turf care’ is the maintenance and usage of different types of turf throughout the year under all weather conditions.
‘Technical turf care’ applies to both ‘fine turf grass’ used in close-mown turf for golf, bowling greens, ornamental lawns, and ‘coarse turf grass’ used on football and rugby pitches, with intensive wear and tear throughout the year.
Grass is the most common and largest plant family. Unless it is of the same variety, it has unique genetic characteristics. Crossing plants and producing hybrids with desirable characteristics may select the best characteristics inherited in the parent species.
Turf Digging And Hydro-mulching Process
During the digging process, some varieties of grass can be cut and lay whereas some other varieties have to be sowed by grass seeds. For example the ‘Axonopus’, Hong Kong local carpet grass is usually laid piece by piece through propagation. This variety of broad leaf blade is very slippery and more satisfactory.
Nowadays, propagating by cuttings like Bermuda, tip way 419 is widely used by grounds men.
The Barclay, Bar credo, Manhattan, Zoysia Japonica Steud and Barry are some of the ryegrass seeds that can be sowed for football pitch use.
For lawns, landscaping and cricket usage, like barrage, Barlow and mondial are some typical examples.
Hydro mulching is more economical in spraying to difficult high reaching area or extensive prestige lawn.
Turf disease can be grouped under two categories, one is activated by contact and the other is systematic from growth. This can be controlled by using chlorothalonil and carbendazim.
Tractor mounted big roll sod harvesters are used for faster and accurate cutting of turf in a wide variety of all weather and ground conditions.
ROLLING, TOP DRESSING AND AERATION, IN RELATION TO QUALITY TURF MAINTENANCE
First of all, one must consider aeration, which involves thatch removal, scarifying, coring, top dressing, drag matting and brushing.
Lifeless turf often results from heavy matting of dead or decaying organic material that gathers at the base of the grass. This leads to a sponginess of the surface, and often a change in colour of the grass. The major causes of these are the lack of aeration, excessive use of nitrogenous fertilizers, over-watering and non-collection of grass clippings during mowing.
Nowadays, recycling of grass clippings is encouraged by using special designed mulching mower blades so that the cut grass is finely clipped into small sections. This assists in rapid distribution in turf and soil in 24 hours or so. These mulched clippings consist of 90% water, 4% nitrogen, 1-2% phosphorous, 1-2% potassium and 1-2 % other miner minerals and trace elements.
These lawn clippers are roughly equivalent to a nitrogen : phosphorous : potassium ratio, which is 4:1:3 lawn fertilizer and by returning lawn clippings to the turf, you can reduce your lawn’s nitrogen fertilizer by 20-30%. In other words, if you are applying fertilizer three or four times annually, it may be reduced to 2 or 3 times annually.
The aeration of rotaries takes continuously cut grass upward, and takes fibber away from the surface rather than pushing it into the surface. Coring performs the modification of subsoil and promotes deep penetration of grass roots.
Slitting allows the grass roots to be cut piece by piece from the main root and propagates each stem through its hair roots to bring more branch stallions.
After coring, slitting, thatch removal and spring tine raking, top dressing with fine soil and rolling the surface to level the lawn is an essential process.
After aeration, it is better to use piston pump boom sprayer or conventional water pump boom sprayer to apply liquid fertilizer and insecticides to relief for soil actives.
If you find the variety of Bermuda grass appears on the blade surface with white and light green spot like the formation of new freshly blade, there may be the case for virus on branch stallions or dry roots.
There are spilt drum rollers, triple rollers and water filled rollers to increase the weight, either trailing or linkage mounted, for leveling the ground.
Different usage requires different kind of cultivators to allow for normal and tear tolerance. One must consider fertilizer inputs, mean performance for compactness, fineness of leaf, tolerance of close mowing and cleanliness of cut.
For instance, for a grass pitch development, the following management schedule is recommended.
1. Foundation development by natural or human process, with drainage system.
2. Subsoil development through top soil cultivation, i.e. ploughing, cultivation and leveling.
3. Basic fertilizer with slow release inorganic fertilizer for improving germination and root development, to achieve a dense sward without undesirable flushes of growth.
4. Laying turf by hand or machine, spray insecticide or liquid fertilizer to improve moisture retention on root and turf density as well as disease resistance and reduction in thatch.
5. Rolling and top dressing are essential for leveling and can improve recovery after renovation for hard wearing.
6. Aeration is essential for maximum absorption of water and nutrients, gaseous exchange and promoting deep roots and healthy sward.
7. Cutting by cylinder mower and rotary mower with grass catcher is essential to achieve a clean cut, particularly with fine leaved varieties.
8. Irrigation either manually, automatically or depend on natural rainfall.
Factors affecting irrigation techniques and timing include grass species, temperature, sunlight, humidity, wind and soil type.
These factors should be achieved according to monthly and seasonal schedules. The whole growing process for a standard soccer pitch development to fully develop deep root penetrations by more than 6 inches prior to use for wear and tear requires more than 9 to 12 months.
NATURE FOUNDATION DEVELOPMENT / HUMAN PROCESSING WITH DRAINAGE SYSTEM
If soccer grass pitches are developed on high ground, the drainage is usually faster than normal. On the other hand, if there is a hard sub-soil layer, water cannot penetrate, modification of soil foundation structure is necessary.
A water penetration test can be made by digging two holes side by side 30 cm deep using a hole digger, pour water into one hole, if water does penetrate, water drain to the bottom and penetrate to the other hole. If this does not happen, modification of soil foundation structure is necessary.
A ’Powadrill’ to 10 inches in depth, or a ‘verti-drain’ with 16 inches depth can enhance the effectiveness of the drainage system and healthiness root development.
Both of the above mentioned process needs a slow speed, and a tractor of 30 hp or more, particularly for ‘verti-drain operation’.
In the drainage process, drainage pipes should drain to an underground drainage system. This is adequate to handle heavy downpours and allow water to drain quickly.
The fiber tissue filtration sheet will hold back the soil and only filtered waterpass through the drainage pipes. This prevents “drain back” through the system.
SUBSOIL DEVELOPMENT WITH TOP SOIL CULTIVATION & BASIC FERTILIZER TO IMPROVE STRUCTURE AND PREVENTION OF SOIL STRESS
Basically, salt free river sand or a combination of sand, clay and peat in a ratio of 7:2:1 or other preferred ratio is sufficient. The higher sand ratio, the better the drainage and more even surface can be achieved.
A soil pH of 5.5 to 6.5 is vital for normal growth of any grass variety.
A tractor can lough and cultivate the subsoil to enhance its absorption of nutrients and trace elements and improve soil structure.
Prior to the laying of the turf, slow release organic fertilizer should be added and separated from hydroseeding.
Inorganic granule fertilizer NPK such as 13+13+21, 15+15+15, Gold N, and slow release fertilizer plus iron, magnesium or zinc, comparatively speaking have longer lasting fertilizing effect than liquid fertilizer.
However, liquid organic fertilizer which is mainly derived from seaweed, according to recent reports, play an important role as a soil conditioner, which increase the soil bacteria count and enable locking up nutrients to become available to grass and stimulate strong rooting and plant health through periods of stress, caused by drought frost or heavy use.
Moreover, it can be spread more evenly over the ground by spraying boom sprayer, tractor mounted, than granule spreading by broadcaster or fertilizer spreader.
Cylinder Mower Cutting & Rotary Mower Cutting
Although all mowers perform the same basic function, there are big differences in use and performance between mower types.
Cylinder mower with 4-8 blades and large diameter such as 8-10 inches are used for sports grounds. For Bowling or putting greens, which require fine and perfectly flat surfaces, cylinder with 8-12 blades with a smaller blade diameter are more appropriate.
Since the cylinder blades are horizontally and parallel to ground surface, cutting an uneven grass lawn results in cutting the grass surface soil at the same time. This will damage the cylinder blade while flattening lawn surface.
There is a front grooved roller for grouping up the grass before the cylinder blades pass through and cut at a very short distance, just install next to the grooved roller. While the small flat roller at rear with skids are for height of cut adjustment for 12 to 60mm about 1/2” to 2”. 1/2” cut is normal for most soccer pitch.
Some cylinder mower with collector and big iron split drum in 2 halves or 3 splits drum in slice pattern are for cutting pattern usage.
For faster and more efficient cylinder mowing, towing cylinder mower of 3, 5 or 7 gangs are used with a speed of 3-11 kph. Hydraulic cylinder gang mower attached to tractors does the same job. Each cylinder mower is normally about 30 inches in width. Do not cut the grass more than 1/3 of the total length of grass. Otherwise, it will reduce growth. To propagate more shoots from the main stem, cut the main stem shorter and more shoots will grow up from the main stem.
Rotary mowers and riding rotary mowers with one or more decks are available for wider cutting width. Some are equipped with a grass collector and can handle difficult situations easily with even the most severe mowing job. The height of cut is adjustable by simple rising of the deck.
Cylinder mowers cut grass more evenly than rotary mower. Rotary means tend to tear off the grass blade, which results in the discoloration of blade tips.
Cylinder mower blades have to be carefully matched and adjusted to the cutter bar. Back-lapping is a very important part of maintaining sharp blades and a good clean. On the other hand, rotary mowers are easier to maintain.
IRRIGATION--AUTOMATIC TIMING, POP UP, SLOW REVERSE CANONS GUNS & HUMIDITY SENSOR
Updated timers can be used to control each particular sprinkler type, to irrigate the lawn as is evaporation takes place and soil dries out.
The soil type, i.e. sandy loam or sandy clay etc. humus content and the drainage, will dictate the application and timing of water for each lawn.
The variety of grass, time and type of fertilizer used will also affect the amount of water used on each particular lawn.
The soil structure should assist the subsoil to be alternately wet and dry, to assist grass roots to take up water moisture from the subsoil, and to feed by themselves.
This means all water and fertilizer for the grass roots should be taken up from the subsoil rather than from the surface layer, so that the roots should get deep penetration down to the subsoil to at least 6-8 inches.
A turf hole cutter can be used to examine the soil and roots profile. A turf doctor is also useful for turf repair at the goalmouth or at any barren area that usually appear due to heavy usage.
The height of cut for soccer pitch is about 3/4”, ruby grounds about 2” and cricket 1/2”, bowling and putting greens are as short as 4mm.
Therefore, volume of water and amount of fertilizer for each type of usage can vary quite a lot, due to many factors and should be adjusted by grounds men according to their experience, all the items mentioned above and basic general growing techniques and local knowledge he processes.
Last but not least, to determine the tractor type, the following features are essential for a good quality tractor. Synchromesh gear box and silent helical gears, 4 wheel drive, low speed and high flat torque, isolated operator’s compartment with rubber mount, cabin windows with four sided opening for tropical climate or hard tip sunlight canopy or soft sided cab, safety ropes, front, mid and rear PTO, hydraulic power take off spool, wheel base and that of H.P. required. For turf usage, at least a 20-30HP tractor, well-balanced, low center of gravity, with a total weight of at least 700kgs is advisable.