CROP CRACK - 04.08.07
By WENDY FEARON
Clarendon Agricare - Prepare For Harvest

Weather conditions over the past week have allowed the remaining acreage of winter barley to be cut. Other cereal crops have ripened quickly in the good growing conditions and some will soon be ready for harvesting weather permitting.

Blight pressure on potato crops remains high and growers are advised to maintain high-risk spray intervals. Due to the season we have experienced, blight sprays have now become quite scarce and product choice may be limited.

Potatoes

Most fields are now at full canopy and growers must pay very close attention to ensure water volumes, spray pressure and nozzle selection are correct to maximize spray penetration of the haulms and reduce spray drift.

Growers should now be using translaminar blighticides or protectants such as SHIRLAN or DITHANE.It is advisable to add a sticker such as Guard in showery conditions.

Where infected patches occur the blighted plants and a sensible area around should be burnt down immediately with a mixture of full rate desiccant and a curative fungicide. The remaining crop must also be treated immediately with fungicide. Inspect crops regularly for the presence of aphids, which transmit leaf roll and mosaic viruses and spray with DOVETAIL or BISCAYA where necessary.

Crops should be desiccated with REGLONE. A newly approved 25% higher rate for Reglone will now enable growers to desiccate even the most vigorous and strongly growing crops. The five litres per hectare total dose could prove invaluable this season to counter re-growth, if lifting is delayed in wet conditions. Potato growers can now use up to five litres of Reglone to desiccate crops this season- a 25% increase over the previously available rate. This new label approval gives growers greater flexibility with their desiccation programmes and a simplified, one product solution for the complete season. Growers could open up the crop canopy with an application at 1.0 l/ha, for example then target the stems and lower leaves with 3.0 l/ha, and still have a further 1.0 l/ha application available to control any regrowth if necessary. SPOTLIGHT PLUS is another option recommended for use after a 7 day interval as a follow-up T2 treatment to the T1 application of diquat and gives more reliable and complete kill of any stems remaining. The best results from SPOTLIGHT PLUS are achieved when applied in bright conditions before late afternoon. It may be applied under wet or dry soil conditions and has a harvest interval of 7 days. However if tubers are to be stored, they should remain in the ground until skins are set.

Cereals

Winter wheat, spring barley and winter oats are ripening quickly and some early crops are almost ready for harvesting. Later crops however will be 2-3 weeks before they are ready to harvest. These should be examined to decide whether or not they require pre-harvest treatment with ROUNDUP GOLD for the control annual and perennial weeds especially scutch, rough stalked meadow grass, thistles etc.

ROUNDUP should be applied when the grain moisture is below 30% which coincides with the hard dough development stage (G.S.87). The safest time is 1-3 weeks prior to harvest leaving at least 7 days between spraying and harvesting. (DO NOT APPLY TO SEED CROPS).

Propionic Acid

PROPIMAX is a liquid preservative which prevents deterioration of stored grain caused by moulds and other bacterial activity. For grain to store safely the moisture content must be below 15%. Higher moisture levels will allow fungal activity to occur causing serious spoilage and the subsequent development of mycotoxins posing a serious risk both to stock and the consumer. The addition of PROPIMAX adds to the energy value of the grain. One tonne of PROPIMAX on 100 tonnes of grain gives an additional energy value equivalent to 1.5 tonnes of barley.

With PROPIMAX treatment, harvesting can take place when there is still surface dampness on the grain. Harvesting can start earlier in the morning and continue later in the evening, giving a quicker more flexible harvest.

Grassland Weed Control

Early autumn is a good time to achieve dock control. In the autumn docks revert back to vegetative growth. This improves translocation of products such as DOXSTAR, FOREFRONT and DOCKMASTER .The result of improved translocation is better root kill. An autumn application is especially important where regrowth has occurred following a spring herbicide treatment. This prevents the regrowing segments of the root from re-establishing before next spring.

Ragwort is a poisonous weed not normally eaten by stock but after treatment with hormone weed killers such as 2,4D or MCPA it becomes more palatable. For this reason the best time to spray ragwort is in the autumn as this gives the weed plenty of time to die and allows a check for the efficacy of the treatment before allocating fields for silage or hay. The addition of a wetter with 2,4D improves the chemical uptake giving better control.

Grassland Re-seeding

The production of top quality grass requires successful establishment and a clean, weed free start. Treatment with either ROUNDUP BIACTIVE or ROUNDUP GOLD will eliminate the old grass sward and provide long term control of perennial weeds such as scutch and docks. It may be applied either before cutting silage (pre cut) or to the regrowth after cutting (post cut).

PRE-CUT Grass crops can be sprayed in August and September before they are either cut for silage or grazed. Ideally the grass to be cut for silage should be between30-60cm (1-2ft) in height. The grass may be grazed or cut for silage from 5 days after applying ROUNDUP. Neither the acceptability by livestock nor the feed value of treated grass is affected.

POST-CUT After cutting or grazing allow a period of 3-6 weeks before spraying. It is important to realise that although ROUNDUP kills the roots of old docks, seedlings may develop from seed lying dormant in the soil. These can be killed with a selective herbicide in the autumn.

Re-seeds should be treated as soon as possible for annual dicotyledons with ALISTELL or REDLEGOR.Both are clover safe and should be applied to clovers after 1 trifoliate leaf and grass after 2 fully expanded leaves.Alistell is most effective on chickweed and also controls a variety of other weeds at the seedling to young plant stage.Redlegor gives no control of chickweed but will control a variety of weeds including buttercup.