Joe,
As I'm sitting here recovering from a bad case of poison oak that I got from scouting last Saturday I thought I might give you a few ideas from my experience. For what its worth, I am a native San Diegan and have hunted this zone every year since 1977.
Let me start by saying, if you hunt public land, San Diego County is not for the faint of heart. Its very difficult to hunt here but once you figure a few things out you can be successful with regularity. Truthfully, as nice as it is to have access to private land, anyone can whack a trophy sized buck in an area where there is little or no hunting pressure. I have much more respect and admiration for the public land hunter who consistently goes out and takes a legal buck on public land.
Personally, I don't think you need all that gear although it does give you an advantage. I have trail cams, ground blinds and tree stands but honestly, any kind of stand hunting drives me nuts. I do not look forward to spending dozens of hours in a tree waiting for a buck to walk by. I much prefer the excitement and intensity one gets from glassing the hills and using the spot and stalk method. What drives me (reluctantly) into a blind or tree stand is a picture of a huge buck on my trail cam. Once I see him I'm on a mission. No other buck will do.
In San Diego's split archery season all my early season kills have been spot & stalk. I just don't see to much buck activity on the trail cams in September. (I set my cameras up in oak groves or near secluded watering holes. I do see lots of does and fawns though.)
To spot and stalk you'll need a good set of binos, a willingness to climb/hike through steep and nasty terrain busting thick sage brush as you go. You'll need a ton of patients too. Expect to see nothing and be pleasantly surprised when you spot even one doe. Look for small patches of bright green vegetation where a spring or small seep may be. Then check them to make sure there is surface water (even a 2" puddle will do) then check for mature buck sign (I.E. splayed 2.5"-3" hoof tracks, rubs on scrub oak branches and larger sized droppings.) Now establish an elevated vantage point that is far away from the seep (minimum 300 yards).
The vantage point needs to be easy to get to (meaning you can access it quietly), the prevailing wind should blow away from the seep and in your face obviously, it should give you good concealment and there needs to be a trail that offers a downward angle of approach to put a sneak on the buck (you may have to make your own trail).
Recognize that your scouting effort probably spooked all the deer out, so make a plan to go back on another morning and glass from the vantage point you chose. Going in, stay out of sight and avoid stepping on dry leaves or breaking twigs. The Gray Ghost sees, hears and smells all but the most disciplined predator, so show him respect or he will make you pay.
In the early morning look for the bucks to be out feeding on scrub oak leaves or new growth in the fire areas. In the midday heat glass the shady spots of trees, bushes and rocks. Learn to glass into the brush rather than around it. Look for the shape of an ear, a leg, an antler or a white patch from their muzzle or rump. (You seldom see a whole deer.)
When you spot a buck count his points to make sure he's a fork or better. You don't want to waste time on a spike. If its preseason be sure you don't spoke him or he won't stick around. Stay put until he leaves or beds down. Then you crawl out. You don't want to spoil your new spot. Now repeat this process 3-5 more times on other hillsides in the area to give yourself some more options before the opener. DO NOT FALL IN LOVE WITH ONE PLACE BECAUSE YOU LIKE THE LOOK OF IT. (I.E. food, water, cover.) If there are no bucks move on!
If its open season, attempt a stalk but be prepared to back off if the wind changes or you can't get to him without making a lot of noise. As it goes with bow hunting, be prepared to blow 90% of your attempts. Its just part of the deal.
This time of year mature bucks stay secluded in their bachelor groups keeping hunkered down in thick sage brush on steep hillside ledges. Again, they typically water on tiny seeps in the hillsides and avoid does and people all together. (To summarize - Other than having access to private property, the secret to hunting SD Co. is to go out and find a your own seep on a brushy hill where there is buck sign. Then put yourself in a position to ambush him during the season.) Its hot, dry, dirty work but I love it!
Towards the end of the early A22 season the immature bucks start to rut and the bachelor groups begin to break up. By the second week of D16 rifle season the big bucks are in rut and they start to get careless. This is a critical time to be out hunting. I hunt all day during the rut and try to get out 3 times per week. Most of my big deer have been killed during this time (*last week of October and the first two weeks of November. Sometimes earlier if the weather turns cool early.) All I do during this period is look for does. Eventually, a horny buck will show up.
At the beginning of the second half of archery season the acorns start to drop in big numbers and my strategy changes again. As a bow hunter you start to lick your chops because you know all the deer will be making a beeline for the nearest oak grove . The deer will be in the oaks eating acorns ravenously for the the balance of the season so all my strategies are centered around figuring out how to ambush deer in the oak groves. (Seriously, its like hunting over bait...only legal.) The two big challenges when hunting in the trees are scent and noise control. In the trees your scent tends to linger so a tree stand really helps. The other problem is piles of dry oak leaves that sound like hand grenades going off when you step on them. So, here too you have to plan ahead about where you are going to hunt just like you do when hunting around a hillside seep. What I do is look for a stand of oaks what are in a big flat area where the trees are well watered. Now look for the trees that have lots of deer tracks under them or are dropping acorns in the greatest numbers. (BTW- coast live oaks and black oaks are the deer favorites. The deer will return to feed. They do so all day long too. I look to see where the prevailing winds are in the early morning hours which tells me how to make my approach, then I rake clean a one foot wide path to my ambush spot. I have ambushed many deer this way using nothing more than a stool and a blind made from dead tree limbs.
Now for the big question , WHERE DO I GO?
Answer, Bucks is where you find 'em.
Here's some ideas for you:
1) The hanglider port above the Buckman Springs exit off I-8.
2) The backside of Vulcan Mt. from S2.
3) McCain Valley
4) La Posta Road
5) North end of Lake Henshaw.
6) Lost Valley near the Riverside Co. border line.
7) Granite Springs from Old Miners Rd. on the east side of Cuyamacha State Park.
8) Boulder Creek between Stallion Springs and indian reservation land.
9) Mt. Laguna Rec. Area.
10) Lake Sutherland
*FYI- Stay off private property! Get a map from the US Forestry Service.
What I just gave you took years of scouting to figure out. I have seen or killed big bucks in all of these areas. Now its up to you. Go out there and do some scouting like lungpopper just said.
Happy Trails!