Plant Material Sampling Procedures for Specific Crops

• Leaf sampling may be undertaken at any stage up to tasselling.
• Leaf samples should not be collected for analysis after pollination.
• For maize plant less than 30 cm tall, sample all the above ground part cut at 3 cm above the soil surface.
• For maize plant greater than 30 cm, but prior to tassseling, sample the whole first mature leaf below the whorl. Mature is completely unrolled from the stalk and consists of formed sheath.
• For maize plant consisting of 50% of ears showing silks, sample the whole ear leaf. Cut off at the base of the leaf, but leaf should not be included. Sample before silks turn brown.
• Samples are taken from 20 or more plants in zigzag pattern across the field.
• Individual leaves should be broken into sections prior to placing in the sample bag.

• Sample the above-ground green plant material.
• The material sampled should be primary growth or re-growth not older than 6 weeks.
• If sampling is from a grazed pasture, particular care should be taken to avoid material from dung or urine patches being included in samples.

• Leaf samples are taken from a 6 to 8 month old leaves between February and April.
• Collect 4 leaves per tree from the alternate sides of approximately 20 trees.

• Samples should be cultivar-specific.
• Sampling should be collected from bearing trees, preferably in the morning when the dew has dried off.
• Leaf samples should be collected behind the fruit on the fruit-bearing terminal shoots.

Citrus type cultivars:

• Easy peelers
• Navels and grape fruit
• Midseasons and Valencias

Leaf sampling periods:

• End of February
• Mid-March
• Mid-April
• Collect matured (5 to 7 month-old) leaves, 3 to 4 per tree from approximately 20 healthy trees and ensure that samples are all not collected from the same side of the tree.
• Leaf samples should be collected behind the fruit on the fruit-bearing terminal shoots.

• Leaf samples collected from different cultivars should be separated.
• The leaf sampling for litchis is done between mid-September and mid-November.
• Collect 4 leaves per tree from the alternate sides of approximately 20 healthy trees selected throughout the orchard.
• The sample can be collected from either of the leaf positions.

• Leaf samples for macadamia must be collected between October and November.
• Collect 4 leaves per tree from the alternate sides of approximately 20 trees, well distributed throughout the field.
• Target the third youngest fully open leaf from 20 homogeneously appearing and well distributed plants throughout the block.

• Leaf analysis is generally done only on trees that are 5 years or older.
• Collect 4 leaves per tree from the alternate sides of approximately 20 selected trees.
• Mark all the trees used for sampling so that samples can be collected from the same trees every year.

• Sampling is conducted between January and March (depending on the pruning time).
• Collect 4 leaf samples per tree on alternate sides of the tree behind the largest fruit from 20 trees.

• Plants can be leaf sampled when they have produced an inflorescence, but before developing a bunch.
• Samples should be taken in February and March
• Target the third youngest fully open leaf from 20 homogeneously appearing and well distributed plants throughout the block.
• Take two squares of lamina (150 x 150 mm) from either side of the midrib at the mid-point of the leaf.