使用多维数组中的键获取值不会返回预期结果

I'm currently trying to loop over an array and only get specific values with key 1, but for some reason it's giving me another array instead of the string value I'm trying to retrieve.

            //using firstElement variable to skip first row of excel sheet
            $firstElement = true;
            foreach ($arrayData as $excelData){

                if($firstElement){
                    $firstElement = false;
                }
                else{
                    $latinName = array_column($excelData, 1);
                    var_dump($latinName);

                    if(strtolower($latinName) == strtolower($target3[0])){
                        echo('target is already in database' . PHP_EOL);
                    }
                    else{
                        echo($latinName . 'should be written to database' . PHP_EOL);
                    }
                }
            }

this is the current for each loop I'm using. The variable arrayData is an array with every result I'm getting from an excel sheet. My goal is to get the specific field latinName from each row.

result from the variable dump is a list of arrays:

[121]=>
  array(7) {
    [0]=>
    string(14) "Knolboterbloem"
    [1]=>
    string(19) "Ranunculus bulbosus"
    [2]=>
    string(7) "Plantae"
    [3]=>
    string(13) "Magnoliophyta"
    [4]=>
    string(12) "Angiospermae"
    [5]=>
    string(14) "Basal eudicots"
    [6]=>
    string(12) "Ranunculales"
  }

My goal is to get every value with key 1 from those arrays and assign them to variable latinName using this code (edited this code to test Mark Bakers answer):

$latinName = array_column($excelData, 1);

But whenever I print out the value from latinName I get another array instead of the String value:

array(17) {
  [0]=>
  NULL
  [1]=>
  string(10) "Poa annua "
  [2]=>
  string(22) "Alopecurus myosuroides"
  [3]=>
  string(22) "Echinochloa crus-galli"
  [4]=>
  string(17) "Apera spica-venti"
  [5]=>
  string(14) "Milium vernale"
  [6]=>
  string(14) "Lolium perenne"
  [7]=>
  string(20) "Agrostis stolonifera"
  [8]=>
  string(15) "Holcus lanatus "
  [9]=>
  string(14) "Avena sterilis"
  [10]=>
  string(19) "Digitaria ischaemum"
  [11]=>
  string(15) "Setaria viridis"
  [12]=>
  string(20) "Setaria verticillata"
  [13]=>
  string(18) "Cyperus esculentus"
  [14]=>
  string(16) "Eragrostis minor"
  [15]=>
  string(13) "Holcus mollis"
  [16]=>
  string(17) "Scirpus maritimus"
}

I don't use PHP that often, but why is my variable latinName getting turned into an array?

Any help would be greatly appreciated and sorry for the messy post.