ISA Soil and Water Management 2

Question 1

What is the primary concern with overwatering established landscape trees?

Accepted Answer

It saturates the root zone, displacing oxygen and creating anaerobic conditions that lead to root suffocation and disease

Answer

It makes the leaves grow too large

Answer

It causes excessive height growth

Answer

It dilutes soil nutrients beyond recovery

Question 2

How does a perched water table form and why is it problematic for tree root health?

Accepted Answer

It occurs at the interface between two soil layers of different texture, trapping water above the finer-textured layer and saturating roots in that zone

Answer

It forms when tree roots grow into a natural spring

Answer

It is caused by underground utility pipes blocking drainage

Answer

It only forms in coastal areas near sea level

Question 3

What is the recommended method for irrigating newly transplanted trees during their establishment period?

Accepted Answer

Deep, infrequent watering that moistens the entire root ball and surrounding soil, gradually reducing frequency as roots establish

Answer

Frequent, light sprinklings every day

Answer

Only water during the first week after planting

Answer

Apply water only to the soil surface beyond the root ball

Question 4

How does road salt (sodium chloride) damage trees growing along roadways?

Accepted Answer

It increases soil sodium levels causing clay dispersion and poor drainage, draws water from roots through osmosis, and direct spray causes foliar desiccation

Answer

It attracts deer that browse on branches

Answer

It only affects trees through splash damage to bark

Answer

It creates acid rain when dissolved in water

Question 5

What is the relationship between soil texture and plant-available water holding capacity?

Accepted Answer

Loam soils hold the most plant-available water because they balance drainage and retention better than sand or clay

Answer

Sandy soils hold the most plant-available water

Answer

Clay soils hold the most plant-available water

Answer

Soil texture has no relationship to water availability

Question 6

Why is the concept of the 'critical root zone' important during construction near trees?

Accepted Answer

It defines the minimum area around a tree that must be protected from soil compaction, grade changes, and root severance to maintain tree health and stability

Answer

It defines where new trees can be planted near the construction

Answer

It marks the area where tree removal is prohibited

Answer

It indicates where irrigation pipes should be installed