The Tropical Fruit Forum

Yes you are right. I have seen the yellow develope as the disease progresses. I hope that its not canker. 

By all means get the County Agent diagnosis. I can not tell you to avert the law/rules. That is your decision.  I Advise you to do whats right for citrus. I love my tress too but if necessary "If thy right eye offend the, pluck it out".  Best advice I can give you is: Call your County Agent....go from there......
.

Your local County Agent is listed under the Govt agencies in phone book
 Sorry no such thing as a phone book any longer......Google ________ County Agent & that should give you a way to get in touch. The procedure for citrus no days is: Keep your citrus as stand alone trees. Do not bring any plants near them that could contaminate them. Use only certified budwood and sterilize tools before working on citrus. Keep your trees well fertilized, watered and control pest. Like humans, healthy ones are more disease resistant than poor health specimens. Some additional info:https://edis.ifas.ufl.edu/pp116  or Google Citrus Canker in Florida.

This does bear a resemblance to citrus canker. Very light at this time. The leaf pic is good. The other pic. Is not very clear but I see canker like spots  in it. I would call my county agen and let him make the determination. If, with all the focus on canker at tbe present, he will determine and take the needed next step. Canker is incurable. Several states have tried without secess, to eradicate it. Fl being one of them. It is subdued for a while and it rears its ugly head again. Its hard to determine canker from pics but here is a pic of canker....compare it to your pics.

Good thoughts. Remember that a healthy graft and scion start with healthy rootstock.

For a novice I recommend budding. Its a little easier imho, and its the right time of the year. If you are in need of a good budding tutorial the fruitmentor vids are as good as they come. Let us know how it goes.

Poncirusguy is right. The enlarged photo shows a union at the base of the tree. Your clarification statement leads me to believe that your tree is in some stage of recovery from a lack of fertilize and water. With adequate water and fertilize I feel that your tree will recover. Its a good size tree and will be a heavy feeder.

It can be done but: It will be tedious and for a new grafter can be frustrating. One of tbe reasons for waiting till rootstock is big enough is it makes it easier to handle, easier to see what you are doing and easier to find budwood of the right size.  That being said I have grafted with rootstock as small as you speak of. Find you some small budwood, use the tbud method and take your time. Make sure your buds are in the right place and have at it. Good luck with it.  When I do this I do it on a bench in the shade with a arm mounted magnifying glass. When rootstock is only 6 inches tall it is very small and spkndly & bark is green and thin.

 Leaf miners looks to be the main culprit.  Use Bayer Systemic to have some control over them. Watch for bulldog catapillars.  They eat leaves. If you are the owner of just one grapfruit tree, keep it watered, fertilized and try to keep pest under control and your tree should be fine.

Clear up the aphid situation and graft different varities to all healthy shoots. You can build a cocktail tree and have fun grafting too. Or.........remove all but the best graft stock and cleft your choice/favorite citrus on it.

I would wait until growth and conditions were right and cleft graft. I find that buds are hard to force when there is a lot of growth above the bud that you install. Remember too the growth habits of buds...make sure this is what you desire. Cleft grafting also does not have the restrictions (timing) that budding does. Good luck with your project.

I mix my Spinosid with horticulture oil and get good results. It depends on several factors...not the least of them is "how immune. to Spinosid he is and his new tolerance to it. Temp & time of day are also factored in. This year I am only using Bayer Nd a hard spray of water every other day....So far so good.