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A knock down golf shot is a really useful shot to be able to play. It is a golf shot that is hit on a deliberately low trajectory, to produce a low, but long, ball flight. This type of ball flight is extremely useful to be able to produce if you are playing in windy conditions. Hitting a normal trajectory golf shot in windy conditions will see the ball fly up into the wind and the ball will be blown off its intended target line, making it difficult to control accuracy. The ball will also be affected by the wind with its length as well.

Shots being played with the wind will fly further than usual and those being played into it will not fly as far. This makes distance control very difficult also. Being able to play a deliberately low trajectory golf shot that will fly underneath the influence of the wind, therefore becomes very valuable as with this shot you will still be able to hit an accurate and well controlled golf shot.
A low ball flight is also valuable to be able to play if you are facing a shot from the trees, or where there are over hanging branches between the ball and the target. A low shot in this situation will allow you to attack your target, rather than having to play safe, or risk a deflected shot.

To play a knock down golf shot, you need to alter your set up position to promote the low flight. Play the golf ball further back in your stance than usual as this will encourage you to connect the club head with the golf ball on the club heads down swing, when the face is more de-lofted, which will produce a lower flight than usual. You also need to place more weight on your front foot than usual and play the shot with your hands forward. To achieve this hand position, create a straight line from your left shoulder, for right handed golfers, down your left arm and then extend this down the shaft of the golf club. This will promote less loft on the club face so that as you strike the golf ball, a low flight is produced.

Pull your left foot directly back from its usual position and this will help you to rotate your lower body towards the target as you swing through impact, allowing your arms to extend towards the target so that the club head swings along the target line, producing a straight golf shot.

Your actual swing needs to be shorter than usual on both your back swing and follow through as you do not want to use your wrists, but rather keep the club head lower than usual. Your back swing will only be around chest to shoulder high, as will your follow through. When you swing, work on keeping the shaft of the golf club and your left arm in as straight a line as possible. Your follow through will be shorter than usual and you want to achieve a laid off position, which means the club head finishes lower than your hand position.

A topped golf shot does have a very low trajectory, but it is a mis-hit not a deliberately hit low shot. A topped shot sees the club head strike only the upper part of the golf ball and the ball does fly low but not very far. A knock down golf shot is a well struck shot that has distance even though it is low.

Knock down golf shots definitely do not fly high. The whole point of a knock down shot is to limit the height of the shot so that you are able to play effective golf shots under the wind or under over hanging branches.

A knock down golf shot is a really effective golf shot to be to play when required. It can help you to retain your accuracy and shot distance when you are faced with difficult conditions or situations, so that you are still able to score really well.