Street tree data from the TreesCount! 2015 Street Tree Census, conducted by volunteers and staff organized by NYC Parks & Recreation and partner organizations. Tree data collected includes tree species, diameter and perception of health. Accompanying blockface data is available indicating status of data collection and data release citywide.
Download the data dictionary for the data set from this link: https://github.com/aswin950/2015-Street-Tree-Census---Tree-Data/blob/main/StreetTreeCensus2015TreesDataDictionary20161102.pdf
1.)Data set: https://drive.google.com/file/d/1PM95Xf0gcpT0krc6bL8PkZqCdJGV0n_-/view?usp=sharing,
2.) Tableau Workbook: https://drive.google.com/file/d/1QOXS1MDnzsi9SkyoAGDWxtqKyhTcjblt/view?usp=sharing
We want to know what are the top 5 rare species in New York City from the street tree census. When the management knows which are the rare species in the city, they can then find the tree’s health status which can be alive, standing dead or stumped. The management can also try to increase the tree count of the top 5 rare species. The top 5 rare species and common species in all five boroughs are shown below in figure 2. The number increases as the color gets darker which as a visualization helps the target audience to get an insight about the data.
I have considered three problems in a tree which are root stone problem, branch light problem and trunk other problem. These three has no problem with an average of almost 90%. So, I would suggest the management to plant more trees with less problem and notice the changes in terms of month and seasons and plant the trees such that they have less tree problems. The horizontal stacked bar conveys the required message with yes and no in the legends with appropriate colors.
We need to know the average diameter of trees in all five boroughs, which includes their status, and month-on-month average diameter in each year. The tiles in the dashboard represent the average diameter and the tree status, whether it is alive, standing dead, or stump. We can also see the borough-wise average diameter in a box plot that includes all the five boroughs in New York City, along with the tree status indicating whether it is alive, dead, or stump. Lastly, there is a trend line graph that displays the month-on-month average diameter for the years 2015 and 2016. All these 3 visualizations can be changed based on the date selected on the top right. The selection of date can be used to notice the seasonal changes with respect to tree health and tree status. These visualizations effectively convey the story to the target audience.
There is one interesting data point that I observed which is when the health status is alive it counts to be 652,173 instead of 652,172 because in the given PDF it says “Field left blank if the tree is dead or stump”. There is only data point with tree status as “alive” and health field with no value. Finally, I have made borough wise health for the trees that are only alive with vertical stacked bar indicating Fair, Good and Poor with different colors along with the percentage which is shown in the below figure 6. Manhattan has the lowest health in terms of Good and with higher percentage of Fair and Poor. Hence, I would suggest the management to appoint more staffs to Manhattan.
Different types of visualization including maps, highlighted chart, vertical and horizontal stacked bar were created using Tableau to answer the research questions. Based on the findings from the visualization suggestions are given to the management for the trees from the street tree census data.