Remove L.esri.query featureLayer from map ESRI Leaflet

Question

Using ESRI Leaflet I am adding markers to the map from an ArcGIS online feature service. I do this using the L.esri.query method similar to:

function slideChange(time1, time2, service) {
    L.esri.query({
        url: service
    }).where("(date_cst BETWEEN DATE '" + time1 + "' AND DATE '" + time2 + "')").run(function (error, pings) {
        trucks = L.geoJSON(pings);
        // remove previously added markers
        removeAllLayers();
        map.addLayer(trucks);
    });
}

Each time I try to call the function I need to remove previously placed markers using leaflet removeLayer() function.

    function removeAllLayers() {
        map.removeLayer(trucks)
    }

The markers are never removed and the map freezes. How can I remove this specific layer from the map using esri leaflet?

Answer 1

@BillChappell suggestion provided me the answer I needed. After adding the L.geojson() variable to a group I was able to clear the layers with a function. Example code...

var active = L.layerGroup();

...

query = L.esri.query({
    url: service
});

query.where("(date_cst BETWEEN DATE '" + time1 + "' AND DATE '" + time2 + "')");

query.run(function (error, pings) {
    trucks = L.geoJSON(pings, { options });
    trucks.addTo(active);
}

active.addTo(map);

...


$("#clearMap").click(function () {
    removeAllLayers();
 }

 function removeAllLayers() {
    active.clearLayers();
};