Effect of Ions on Plant Growth

Ion	High Concentration	Low Concentration
Hydrogen	Low pH - root damage	High pH - less growth; reduces other nutrients
Calcium	Reduces growth; reduces other nutrients; yellow leaves	Reduces growth; fewer and smaller leaves; fewer flowers
Chloride	Stunts growth, browning of leaves	No Effect
Nitrate	More large, green leaves; less flowers	Fewer, smaller leaves; light green, yellow or brown leaves
Sulfate	Small leaves; less growth; yellowing leaves	Yellowing along veins and edges of leaves

Conclusion

1. Using information from the data tables, what comparisons can you make about the chemicals in the leaves of the healthy and unhealthy plants?
2. What plant observations and soil conditions provide evidence of healthy plant growth?
3. What observations from soil conditions and the table on Effect of Ions on Plant Growth provide evidence to explain why plant “U” is unhealthy?
4. What must be added to the soil to change soil conditions from unhealthy to healthy? What other factors not studied might have caused the plant to be unhealthy?
5. Explain how this could cause the observed effects.