Anti-fungus chemicals

Is it okay to spread the chemicals on my lawn at this time of the year? The fungus is causing brown spots from the summer till now. I live in Houston Texas. Thanks.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.