Yes, there is a difference between ‘structure’ and ‘cover’ – and yes, you need to know the difference! Both require a different approach, a different boat position and a different selection of baits definitely come into play. You need to understand what you are fishing, interpret accordingly and execute with intent.
So how do you make the differentiation? Simple, ‘Structure’ is the variation found in the topography of a lake or dam. These variations include contour changes, river channels and humps, while ‘Cover’ is the physical growth or habitat found within a body of water, namely vegetation, timber and rock. Cover plays an extremely vital role in attracting baitfish and other fodder to an area, in turn determining the population of bass an area will support. Therefore your main objective is locating the convergence point between structure and cover - this is the sweet spot!
Targeting structure is all about boat positioning. You need to position your boat in a way that ensures you are effectively covering as much water as possible while pinpointing the fish's exact location. A parallel approach is your most productive way of targeting contour changes such as break lines or river channels. Positioning your boat along the contours makes isolating that magic depth reasonably predictable. I will normally start my hunt on a drop-off with a fast moving, deep diving crankbait. This puts any active fish in the boat and by changing the angle of my cast to the deeper contour, gives away the position of any suspended fish. Once I have made a few mental notes with my primary approach, I will slow down slightly with a slow-rolled spinnerbait. The effective zones will now be bombarded with my yo-yo style retrieve, once again making sure any fish suspended just off the bottom are not being ignored. If my offerings are not quite forcing the bites I am looking for, I will break all my rules and resort to a Carolina Rig or Drop-Shot Rig. If you approach every break-line with a similarly planned attack, making sure you mentally record the depth of each bite, I guarantee you will put a higher percentage of these fish in the boat than what you are used to!
When it comes to humps, your angle of approach is vital. Once again I will start with a crankbait and fire it at the structure from every available angle until the fish react, and then repeat. By changing angles you are targeting first of all, a different section of the structure, as well as mixing up the depths at which your crankbait runs. Your crank will bottom out on the hump and when thrown to either side of the zone will mop up any suspended fish hovering off the edges. Sometimes bass just want a crank at a particular angle, so make sure you are always experimenting. Should there be no takers, once again let the plastics double check!
Not all structure is created equal, as mentioned the combination of structure and cover is what you should really be looking for as well as structure within structure. What I mean by this is the meeting point or influence of more than one type of structure, for instance a hump adjacent to a river channel or an intersection between a creek channel and a main channel.
Variations of cover are never ending; to summarize, the major categories of cover would include vegetation, timber and rock. The major defining factor when fishing one of these forms of cover is once again finding the productive depth holding bait and bass. This brings structural variations back into the game, so understanding what the contours are doing in relation to the cover you are fishing will narrow down your search.
My personal favourite cover is undoubtedly submerged vegetation. Unfortunately this is often dependant on recent water level fluctuations and can therefore become unreliable at times. When I fish submerged vegetation my aim is to cover as much water as fast as possible, taking note of any depth changes until I find a concentration of fish. Lipless crankbaits and jerkbaits are my ‘go-to’ baits as they make fish bite, giving away their position. Often the first few fish will commit and then the bite will slow if you can't keep them going. I will then go back through the same area with a plastic jerkbait or weightless senko, taking stock of the remaining fish. Targeting visible vegetation is no technical deal, topwaters, spinnerbaits and plastics all put 'em in the boat. Vegetation normally holds baitfish so let your choice of bait reflect this!
Timber comes in many shapes and sizes and is widespread throughout most dams in one form or another. My initial decisions on which timber to target are based are on few simple guidelines. If I am fishing shallow timber I will look for timber in the dirtiest water I can find. This allows me to get shallow, use bigger baits on heavier line and means weather conditions play less of a role. When prospecting off-shore timber and brush piles, I will focus on the timber closest to the nearest break line. This means the fish that are using the break line as a daily migration route have less water to cover to find suitable feeding zones. I normally start my timber missions with slow sinking senko style bait, which picks off any suspending fish as well as any fish not sitting tight to the cover. I will then switch up to a Texas rigged bait or pitching jig to force feed any stubborn fish sitting deep in the cover.
Rock structure is another great habitat for natural forage, namely crabs and baitfish. My favourite ways to get results on the rocks include the use of suspending jerkbaits on vertical rock faces, Football jigs on offshore rock piles and rocky banks, as well as crankbaits along the rip-rap style banks. The winter months are your best bet for rocky areas as the rocks hold heat, creating slightly warmer water within close vicinity to the rocks. A temperature change, even as slight as a degree or two can sometimes make a huge difference!
I now trust you have clearer understanding between structure vs.cover and the differences in tactics they call for. As similar as the two may be, they are completely different, yet have so much in common.