Neutralisation of herbicides. Effects on wall vegetation

The chemical control of wall vegetation growing on monuments has been stated as a suitable instrument of conservative intervention. However, often the use of herbicides has not been the most suitable, endangering either the environment or the monument in question. In particular, when dealing with limestone monuments, the chemical control has to be made very carefully because all the carbonate rocks are particularly sensitive to the weathering action of acids. Thus, to prevent this damage, two acid herbicides were neutralised with potassium hydroxide. This neutralisation did, in fact, decrease the damage caused by their acidity on the limestone. This paper deals with the effects of these neutralised herbicides on higher plants. Several experiments were made to determine whether the efficiency of the herbicides was affected. Also, the neutralisation did not affect the ability of the herbicides to eliminate the wall vegetation.