We would like to know why after several years all these arborvita died? And why 2 out of 3 of this short shrub died.

Hi Michelle,

Thank you for reaching out to the OSU Extension office. After reviewing the photos of your arborvitae, the causes may be due to several potential factors, including winter damage.

To assist you further, we’ve included a resource from Penn State University Extension that outlines common arborvitae issues and their possible causes:
https://extension.psu.edu/the-mighty-arborvitae

For a more detailed assessment, additional information would be needed. You’re welcome to contact your local OSU Extension office, where your county’s ANR educator can provide insights specific to your area. To find your local office, simply search for your county name followed by .osu.edu in your web browser.

Additionally, feel free to call me at<personal data hidden> or email me at <personal data hidden> if you'd like to discuss this further.

Best,

Marina 

OSU Extension Greene County
100 Fairground Rd, Xenia, OH 45385
<personal data hidden> Office /<personal data hidden> Direct
<personal data hidden> / greene.osu.edu