IOIA Technical Advisory Panel

Cane Berries
Summary: Cane berries, often called brambles, in the genus Rubus, grow on perennial plants with a semi-vining habit, that is, not vines like grapes, where the advancing growth wraps around objects (or overly stationary inspectors!) but usually vigorous multi-stemmed, often thorny, plants, emerging from a dense, semi-woody crown. Typically, though not always, the emerging growth is upright is aspect but can be easily trained to trellising of many configurations. Most, but not all, varieties flower and fruit on second year growth after a dormant period. Crops most commonly include blackberries and raspberries, with many varieties, cultivars, or hybrids on the market. There are other cane berries out there, but their occurrence is usually of local interest only.

In most parts of the country, cane berries are grown as perennial plants, though in some warmer climates, they are transplanted as crowns and a crop harvested within a year, then the plants are removed. This is an uncommon practice, relative to all cane berry production in the US, but is gaining in frequency along the central California coast, for example. A relatively new activity in many parts of the country is the growth of raspberries in cold frames, gaining access to early markets and increased production, in some instances. Pollination is more difficult under this scenario, but need not be prohibitive.

Areas or subtopics of importance to inspectors:

Common pests
Weeds: Grasses are particularly troublesome as they will easily invade the crown area and reduce the water available to the crop, raise the humidity in the canopy (increasing the likelihood of pathogen development), and utilize the nutrient sources provided to the crop. Close manual cultivation, mowing and robust soil preparation prior to planting are the dominant and most successful strategies. Mulches can also work in some situations, though they may increase the chances for root rots as well, depending on the situation.

Pathogens:
Roots: Verticillium wilt, Phytophthora root rot, and Armillaria (in plantings adjacent to or in ground previously used for tree production).
Canes: Cane spot and blight, cane botrytis and canker, fire blight.
Leaves: rust, leaf spot, powdery and downy mildews, and Pseudomonas blight.
Fruit: Botrytis, Many varieties are also susceptible to several viral infections and nematodes.
Of course, all pathogens require the typical ‘Big 3' conditions: susceptible host, inoculum, and favorable environmental conditions for growth.

Invertebrates: include mites, particularly the two-spotted spider mite and the berry mite (often called the blackberry mite); leaf rollers, crown borers, aphids, leafhoppers, and sawflies. There are several other insect and mite pests that may be particularly troublesome from region to region.

Vertebrates: Birds and deer (and the occasional fruit thief) are common and potentially devastating pests.

In general, solid fertility management, cultural practices, variety selection and thoughtful planning minimize the impact of pests on the crop. Inspectors should ask questions about each of these features in and of themselves as well as in relation to pest management issues since it will show the degree to which the grower is engaged with the crop.

These crops tend to be moderate to heavy feeders, requiring substantial organic matter or concentrated fertility amendments to produce well in most areas. Expect a proactive fertility program, with phosphorus, potassium and calcium figuring prominently.

Q & A

No questions have been received as of yet.