Praktiska observationer kring islńggningsskador pň sportytor i Sverige

H÷fundur┌tgefandi┌tgßfußr┌tgßfusta­ur
Dahlsson Sven-OveB˙na­arfÚlag ═slands, BŠndaskˇlinn ß Hvanneyri, Rannsˇknastofnun landb˙na­arins, Rannsˇknast÷­ SkˇgrŠktar rÝkisins, Tilraunast÷­ hßskˇlans Ý meinafrŠ­i, Vei­imßlastofnun1989ReykjavÝk
Rit┴rgangurT÷lubla­Bls.
B˙vÝsindi231-34

gr-buv2-sod.PDF

Frß vefstjˇra: Greinina Ý heild sinni er a­ finna Ý pdf-skjalinu hÚr a­ ofan

ABSTRACT

Practical observations on ice-encasement damages on sports turf in Sweden

Limited scientific attention has been paid to winter damages on sports turf in Sweden. In practice, the biotic factors seem to be better known than the abiotic.

There are no statistical data available on the extent of ice-encasement and waterlogging damages. Data on the overwintering in leys give some information but cannot be directly applied to sports turf. In the latter you also have to include factors like intensive wear, low mowing height, high Nfertilization and a stand which is often dominated by one species - most frequently Poa annua.

When building sports turf it is of vital importance to secure effective surface runoff and adequate drainage. In maintenance work, frequent hollow fining and sand dressing are most important in creating a dry surface layer in order to avoid ice and water damages.

There seem to be no trials done on ways to expedite the melting of ice and snow. In practice various methods have been tried:

1. Urea gives a good effect but the quantity of N applied is questionable from an environmental point of view.

2. Basic slag was used in earlier days when it was available. It is not recommended since old turf often has too high P-values.

3. Sand-dressing has good but limited effect. Can also be recommended for other reasons.

4. Organic dressings (poultry manure, peat etc.) give some effect, but are negative because of the building up of organic material in the top layer. The material should be removed after snow melting.

5. Ashes, coal residues etc. give effect but are difficult to handle. The material should be removed.

6. Mechanical removal demands much labour and is difficult to do. It should be done only during periods when the ice can be easily loosened from the turf.

It is stressed that ice-encasement and waterlogging damages in sports turf are probably greater than generally considered. Trials on how to reduce the damages are highly needed.

Key words: ice encasement, sports turf, waterlogging.

YFIRLIT

Hagnřtar athuganir ß svellkali Ý Ý■rˇttav÷llum Ý SvÝ■jˇ­

Kalskemmdir ß Ý■rˇttav÷llum Ý SvÝ­■jˇ­ hafa lÝti­ veri­ rannsaka­ar. Menn hafa frekar fengist vi­ rotkal en skemmdir af v÷ldum umhverf s■ßtta. Engar heimildir eru til um svellkal Ý Ý■rˇttav÷llum og skemmdir ß t˙num er ekki hŠgt a­ tengja skemmdum ß Ý■rˇttav÷llum. ┴ Ý■rˇttav÷llum koma til ■Šttir svo sem slit, lßg slßttuhŠ­, mikill k÷fnunarefnisßbur­ur og sv÷r­ur me­ einni rÝkjandi grastegund, oft varpasveifgrasi. Vi­ byggingu Ý■rˇttavalla er nau­synlegt a­ tryggja gott afrennsli og nŠgilega ■urrkun. ═ vi­haldi er mikilvŠgt a­ gata oft og sandbera vellina til a­ ■urrka yfirbor­slagi­ og for­a ■annig svellkali.

Engar beinar tilraunir hafa veri­ ger­ar til a­ flřta brß­nun svella, en menn hafa prˇfa­ eftirtaldar a­fer­ir:

1. Ůvagefni, strß­ ß svellin, hefur gˇ­ ßhrif, en umhverfisßhrif k÷fnunarefnis eru vafas÷m.

2. Thomasfosfat var ß­ur fyrr strß­ ß svell en ekki mŠlt me­ ■vÝ vegna ■ess a­ gamall sv÷r­ur er oft fosfˇrrÝkur.

3. Sandstrßning hefur ßgŠt en takm÷rku­ ßhrif. MŠlt er me­ ■essari a­fer­ einnig af ÷­rum ßstŠ­um.

4. Strßning lÝfrŠnna efna (b˙fjßrßbur­ar, mˇs o.fl.) hefur ßhrif en er neikvŠtt vegna ■ess a­ ■a­ bŠtir lÝfrŠnum efnum Ý sv÷r­inn og ■arf ■vÝ a­ fjarlŠgja ■a­ eftir brß­nun.

5. Aska og gjall hefur ßhrif en er erfitt Ý me­f÷rum og Štti a­ fjarlŠgjast eftir brß­nun.

6. ═sru­ningur er vinnufrekur og erfi­ur. SlÝkt Štti a­eins a­ framkvŠma er svell eru laus frß j÷r­inni.

Svellkal og flˇ­skemmdir ß Ý■rˇttav÷llum eru lÝklega algengari en almennt er tali­ og rannsˇkna er ■÷rf ß ■essu.