Tissue Sampling Procedure
Plant tissue analysis
is primarily used to detect nutrient deficiencies and to
evaluate responses to fertilizer additions and other
cultural practices. Both soil testing and plant analysis
are useful diagnostic tools and one should not be used
in lieu of the other. Similar to soil testing, an
important aspect of plant analysis is sample collection
and handling. Plant composition varies with age, plant
part, plant condition, variety, and environmental
factors. Therefore, it is essential that proper sampling
protocols be followed.
These guidelines should be consulted prior to sampling
any crop to ensure proper interpretation and meaningful
results. Separate sampling and analyses should be
conducted in those areas that appear to differ greatly
from the rest of the field. This same approach should
also be used when conducting diagnostic or
It is also important to identify what not to include in
a tissue sample. Plants that are under stress, or
mechanically or insect damaged, or disease infested
should not be sampled. Finally, it is desirable to
withhold sampling during, or immediately following
(i.e., a few days), an irrigation event.
Use a clean container such as a paper bag or a plastic
pail when collecting a tissue sample. Never use a metal
container due to the risk of sample contamination. Avoid
placing tissue samples in a plastic bag unless the bag
is vented or the sample is refrigerated.
Once a tissue sample has been collected, it should be
delivered to the laboratory as soon as possible. Do not
store plant tissue samples in air-tight bags or at room
temperature. Keep plant tissue samples cool
(refrigerator temperature) but do not freeze.
Accurate plant sampling requires experience and
knowledge, therefore, the use of trained and experienced
samplers is strongly recommended.
Desired sample locations for common crops and a table
presenting an outline the appropriate sample times,
plant parts, and sample sizes pertaining to plant tissue
collection for various crops follow.
Tree S-1 Model
Tree S-2 Model
Tree S-3 Model
Vine Model - Prior to Full Bloom
Vine Model - Full Bloom
Vine Model Petiole