Re-Vegetation Research Project Duck Creek

Report number 1 on the results of re-vegetation by means of hydromulching at Duck Creek Farm

The site

A northerly facing cut face of an angle exceeding 45 degrees approximately 90 x 2.5 metres. Due to the northerly aspect and the steep angle the site tends to remain dry even during periods of high precipitation.

Date of application
The hydromulch was applied on the 1 June 2006. It is to be noted that the seeding was done at the beginning of winter in the the Southern hemisphere

Seed mix applied
Commercial Rye, clover mix (Lolium perenne and Trifolium repens) at a rate of 9 kg
Additional seed mix (described below) at the rate of 2.6 kg

The seed was applied together with 20 kg wood fibre mulch, 10 kg cellulose fibre mulch, 9 kg fertilizer, 250g potassium humate and 750g guar gum tackifier per 200 square metres of surface area.

The composition of the additional seed mix.
Linseed (Linum spp) 10 kg
Agrostis capillaris (Common bent, Cultivar Punawai Brown Top) 8 kg
Cynodon dactylon (Bermuda grass) 8 kg
Plantago lanceolatus (Cultivar Tonic Plantain) 4 kg
Oats (Avena sativa) 5 kg
Trifolium pratense (Cultivar Sensation Red Clover) 4 kg
Lotus pedunculatus syn. Lotus major 1 kg

Evaluation of the site on the 5 July 2006
During the four weeks following application the site received frequent and adequate precipitation. Cool moist conditions and numerous night frosts were recorded during the entire period.

Mechanical support given to the bank by the hydromulch has been good, the mulch has maintained excellent adhesion to the surface in no areas whatsoever has it washed off, even on the steepest slopes. Only on the steepest driest sections of the slope has there been some mechanical failure where whole sections of the bank have become dislodged together with their mulch coating. Under no circumstances could the strength of the mulch or similar product have prevented this. Such damage is very minimal as can be seen on the accompanying photo number 1.

On inspection of the site it was found that a reasonable degree of germination has already taken place in particular on the lower third of the slope where the conditions are more favourable for plant growth because of the lesser angle of the slope and higher moisture content of the soil. On the upper slope although somewhat sparse germination had taken place. To date only the quick free germinating species Lolium perenne (Rye) and some Agrostis capillaris (common bent) have germinated.
The more northwest facing sections of the site have shown slightly inferior results, this is no doubt due to the fact that they receive more sun and dry out more quickly. This can be clearly seen in the accompanying photo numbered 1.

In conclusion
In general the results so far are good. Germination of the other species would be expected to occur somewhat later after the germination of the rye (Lolium perenne) and brown top bent (Agrostis capillaris), the Cynodon dactylon as late as in late spring or early summer. Although the hydromulching was done approaching the shortest day and considering the cold conditions including night frosts, the time of year does provide continuous adequate moisture to support initial germination and growth, which in the long term might be of benefit. At times of the year when day lengths are longer and temperatures are higher, conditions more favourable to germination the moisture content of the soil may be insufficient to support both germination and growth. Only further experimentation will give us the answers as to which is going be the best time of year to undertake such remedial work.

Michael Hickman
06.07.06