Household and block level influences on residential fertilizer use

Abstract

Urban and suburban lawns make up a large share of land use in the US. Maintaining lawns to fulfill aesthetic norms has environmental consequences. In this analysis, we examine household decisions to apply nitrogen-containing lawn fertilizer. Using survey data of 298 households in Nashville, Tennessee, we first examine the prevalence of fertilizer use and the rate of annual nitrogen applied. We find that the resulting distribution is skewed, with the top 20% of the sample applying 56% of the total share of nitrogen. In contrast to this subset of “intensive” fertilizers, 93% of households applied at or below levels recommended by landscaping professionals, challenging the assumption that the over-application of fertilizer is widespread. We employed multi-level modeling to examine the relative importance of household- and block-level characteristics on fertilizer use and the intensity of use. Consistent with prior work, we find that the desire for a green lawn is a significant predictor of fertilizer use. However, we also find that living on a wealthy block and living near others who value a green lawn independently predict fertilizer use. In addition, we observe that intensive fertilizing households tend to be less wealthy than others on their block, suggesting the possibility of an aspirational dimension to fertilizer use. Finally, we find evidence that environmental concern is associated with less intensive fertilizer use, suggesting that households may be willing to take some steps to mitigate the impact of their lawn care on the environment.