Lecture 2- Winter wheat Flashcards
How do you identify wheat?
Small hairy auricles
How do you identify barley?
Large overlapping hairless auricles
How do you identify oil seed oats?
No auricles
What is most wheat used for in the uk?
Livestock feed
What is the average UK yield for winter wheat?
8.5T/ha
What is the average yield for first wheat following a break crop?
9-10t/ha
What is the average yield for second wheat, wheat following wheat?
8-9t/ha (1t/ha less)
Traditionally how many tonnes of winter wheat are exported by the UK each year?
3-4 million tonnes
Where are the main destinations for the UK for exporting winter wheat?
Spain (20-30%) Algeria Morocco Portugal Egypt
Why is it advisable to avoid drilling too early? (Early September)
4 reasons
All weeds germinate in crop (no time for stale seed beds)
Very high levels of fungal disease
High numbers of aphids
Higher risk of lodging in spring
What are 3 examples of fungal disease in winter wheat?
Take-all
Eyespot
Mildew
When is the drilling date for first wheat?
Mid-late September
When is the drilling date for second wheat crops?
Mid October due to higher risk
When is black grass a problem during the year?
Late October (needs good soil management)
What is the calculation for seed rate?
Thousand grain weight (g) x target plant population (m2)
—————————————————————
Expected plant establishment (%)
What is systematic fungicides?
Some early control of foliar diseases
What is systematic insecticides?
Protect against early insect damage (e.g. Aphids)
What is the desired drilling depth for winter wheat?
3-5cm
In what circumstance would you require 3cm soil coverage over a winter wheat seed?
If using a pre-emergence herbicide
In what circumstance would you need 5cm drilling depth for winter wheat?
Why?
If the top soil is very dry and drilling early
To allow access to moisture
How long do you have to apply pre-emergence herbicide after drilling/rolling?
Within 48hrs
What are pre-emergence herbicides?
What do they target?
Selective herbicides
Targets weeds when small during the seedling stage
When’s best to use pre-emergence herbicides for winter wheat?
Mid to late autumn
What’s the 3 problems with waiting until weeds are developed when using herbicides?
Harder to kill
Yield already lost
May have produced seeds
What conditions lead to high risk of slug damage to crops?
5 answers
Wet weather Clay soils Following oil seed rape High trash content on soil bed Cloddy soil
How to you break up clods and consolidate seed beds?
Cambridge roller
At what growth stage are slugs an issue?
High risk before growth stage 20s (GS20s)
What does BYDV stand for?
Barley yellow dwarf virus
What crops does barley yellow dwarf virus attack?
Deals such as barley, wheat and oats
How do you control barley yellow dwarf virus?
2 answers
Use systematic insecticide seed treatment
Don’t drill too early
What are the main pest threats to cereal crops?
Slugs and aphids carrying Barley yellow dwarf virus
When are higher seed rates required?
Why?
Later drilling
Less tillers and lower establishment
