Abstract

There was a high incidence of death among the second-year (fruiting) canes in many Scottish raspberry plantations in spring 1962. Varieties differed considerably in the amount of damage which they suffered, and the varieties and seedlings which habitually shed their leaves late in the first year of growth were more prone to damage than those which shed them early. Observations on differences in the incidence of cane death in cultural trials indicated that the damage was usually greatest where plants were given a wide spacing and where high rates of manuring were used. The manures which had the most influence were ammonium sulphate and farm-yard manure. It is suggested that wide spacing and the use of the organic manure produced these effects by influencing the plants’ water supply. Significant coefficients of correlation were obtained between the incidence of cane death and the yields subsequently recorded, but it is concluded, particularly in the case of the variety Malling Exploit, that a considerable yield reduction must have been caused by some kind of damage having a distribution similar to that of the cane death. It is considered that possession of a greater level of hardiness than that present in any of the raspberries now commonly grown could prove to be a very valuable yield component in a new variety.