Certified Crop Adviser with Sustainability Specialty Agroforestry & Trees on Farms for Sustainability: practice questions

1 · Tree-crop interactions: competition and facilitation · medium

In semi-arid agroforestry with trees close to crops, the resource for which competition is usually most limiting is:

1. Water
2. Light
3. Carbon dioxide
4. Oxygen

2 · Tree-crop interactions: competition and facilitation · medium

A practice that reduces below-ground competition between boundary trees and crops is:

1. Planting the crop closer to the tree trunks
2. Root pruning or trenching along the crop side
3. Adding more irrigation only to the trees
4. Removing all leaf litter from the field

3 · Silvopastoral and silvoarable systems · medium

Intake of Leucaena leucocephala fodder by livestock is limited mainly by its content of:

1. Gossypol
2. Ricin
3. Mimosine
4. Solanine

4 · Silvopastoral and silvoarable systems · medium

An important animal welfare benefit of trees in silvopasture is:

1. Removal of all need for water
2. Faster weight gain from bark
3. Protection from all diseases
4. Shade that reduces heat stress

5 · Silvopastoral and silvoarable systems · medium

In silvoarable design, north-south tree rows are often preferred because they:

1. Block all sunlight from reaching the crop
2. Share light more evenly across the day
3. Allow trees to grow without any pruning
4. Remove the need for any machinery access

6 · Agroforestry for soil fertility and erosion control · medium

Trees on farms can improve soil phosphorus and potassium supply mainly by:

1. Fixing phosphorus and potassium directly from the air
2. Creating new phosphorus in their roots
3. Recycling nutrients from deep layers in litter
4. Converting nitrogen into potassium

7 · Agroforestry for soil fertility and erosion control · medium

The Sloping Agricultural Land Technology (SALT), developed in the Philippines, uses:

1. Terraces cut by machine without plants
2. Plastic mulch laid over the whole slope
3. Burning of residues before each new crop
4. Contour hedgerows with crops between

8 · Agroforestry for soil fertility and erosion control · hard

Research in eastern Zambia found maize after Sesbania improved fallows compared with continuous unfertilised maize gave:

1. Lower yields, due to nitrogen loss from the fallow
2. Identical yields, as fallows add no nitrogen
3. Higher yields, but below fully fertilised maize
4. Yields higher than any fertiliser treatment

9 · Agroforestry for livelihoods and markets · medium

A recurring problem for farmers growing poplar for timber in north-western India has been:

1. Price collapse when many farmers harvest at once
2. A permanent ban on poplar wood processing
3. Poplar failing to grow on any irrigated or canal-fed land
4. Prices rising forever with no fluctuation

10 · Agroforestry for livelihoods and markets · medium

Farmer-managed natural regeneration, which spread widely in Niger from the 1980s, involves:

1. Protecting and pruning regrowing native stumps
2. Planting exotic eucalyptus in dense, even-aged blocks
3. Clearing all trees to expand millet and sorghum fields
4. Importing tree seedlings from overseas nurseries